The sensitive balance between five-coordinate carbene and six-coordinate carbyne ruthenium complexes formed from ruthenium vinylidene precursors

Article abstract of DOI:10.1021/om010422x

The reaction of the dichloro(vinylidene)ruthenium compounds [RuCl₂(=C=CHR)L₂] (R = Ph or tBu and L = PCy₃ or PiPr₃) (1a-d) with [H(OEt₂)₂]BAr_f (BAr_f^- = [B{C₆H₃ (CF₃)₂3,5}₄]^-) resulted in the attack of the proton at the C_β carbon atom of the vinylidene ligand and afforded the corresponding cationic, five-coordinate carbyneruthenium complexes [RuCl₂(≡CCH₂R)L₂]BAr_f (2a-d) in almost quantitative yields. The protonation of the carboxylato derivatives [RuCl(κ²-O₂CR)(=C=CHPh) (PiPr₃)₂] [R = H (3a), CH₃ (3b), or Ph (3f)] with [H(OEt₂)₂]BAr_f led to the formation of the five-coordinate cyclic carbene complexes [RuCl{=C(CH₂Ph)OC(O)R}(PiPr₃)₂]BAr_f [R = H (6a), CH₃ (6b), or Ph (6f)], which are formed via nucleophilic attack of the carboxylato ligand to a cationic carbyneruthenium intermediate. The protonation of the related vinylidene compounds [RuCl(κ²- O₂CR)(=C=CHPh)(PiPr₃)₂] [R = CH₂F (3c), CHF₂ (3d), CF₃ (3e), C₆H₄NO₂-4 (3g), C₆H₄NO₂-2 (3h), C₆F₅ (3i), and C₆H₃(NO₂)₂-2,4 (3j)] with [H(OEt₂)₂]BAr_f gave an equilibrium mixture of the carbyne [RuCl-(κ²-O₂CR)(≡CCH₂ Ph)(PiPr₃)₂]BAr_f (5c-e, 5g-j) and the isomeric, cyclic carbene complexes [RuCl{=C(CH₂Ph)OC(O)R} (PiPr₃)₂]BAr_f (6c-e, 6g-j). The position of this equilibrium significantly depends on the basicity of the carboxylato ligand. The six-coordinate cyclic carbene complexes [Ru(κ²-O₂CR¹){=C(CH₂Ph)OC(O) R²} (PiPr₃)₂]BAr_f [R¹ = R² = CHF₂ (7a), CF₃ (7b); R¹ = CF₃, R² = H (7c)] were obtained on protonation of the precursors [Ru(κ¹-O₂CR¹) (κ²-O₂CR²)(=C=CHPh) (PiPr₃)₂] (4a-c) with [H(OEt₂)₂]BAr_f. Both 7a and 7b undergo a fluxional process in solution resulting in a κ¹/κ² interconversion of the carboxylato groups. The crystal and molecular structures of 2b, 5e, and 6a were determined by X-ray crystallography.

Full text of DOI:10.1021/om010422x

3672
Organometallics 2001, 20, 3672-3685
Th e Sen sitive Ba la n ce betw een F ive-Coor d in a te Ca r ben e
a n d Six-Coor d in a te Ca r byn e Ru th en iu m Com p lexes
F or m ed fr om Ru th en iu m Vin ylid en e P r ecu r sor s†
Pablo Gonza´lez-Herrero, Birgit Weberndo¨rfer, Kerstin Ilg, J ustin Wolf, and
Helmut Werner*
Institut fu¨r Anorganische Chemie der Universita¨t Wu¨rzburg, Am Hubland,
97074 Wu¨rzburg, Germany
Received May 21, 2001
The reaction of the dichloro(vinylidene)ruthenium compounds [RuCl2(dCdCHR)L2] (R )
-
Ph or tBu and L ) PCy3 or PiPr3) (1a -d ) with [H(OEt2)2]BArf (BArf ) [B{C6H3(CF3)2-
3,5}4]-) resulted in the attack of the proton at the Câ carbon atom of the vinylidene ligand
and afforded the corresponding cationic, five-coordinate carbyneruthenium complexes [RuCl2-
(tCCH2R)L2]BArf (2a -d ) in almost quantitative yields. The protonation of the carboxylato
derivatives [RuCl(κ2-O2CR)(dCdCHPh)(PiPr3)2] [R ) H (3a ), CH3 (3b), or Ph (3f)] with
[H(OEt2)2]BArf led to the formation of the five-coordinate cyclic carbene complexes [RuCl-
{dC(CH2Ph)OC(O)R}(PiPr3)2]BArf [R ) H (6a ), CH3 (6b), or Ph (6f)], which are formed via
nucleophilic attack of the carboxylato ligand to a cationic carbyneruthenium intermediate.
The protonation of the related vinylidene compounds [RuCl(κ2-O2CR)(dCdCHPh)(PiPr3)2]
[R ) CH2F (3c), CHF2 (3d ), CF3 (3e), C6H4NO2-4 (3g), C6H4NO2-2 (3h ), C6F5 (3i), and C6H3-
(NO2)2-2,4 (3j)] with [H(OEt2)2]BArf gave an equilibrium mixture of the carbyne [RuCl-
(κ2-O2CR)(tCCH2Ph)(PiPr3)2]BArf (5c-e, 5g-j) and the isomeric, cyclic carbene complexes
[RuCl{dC(CH2Ph)OC(O)R}(PiPr3)2]BArf (6c-e, 6g-j). The position of this equilibrium
significantly depends on the basicity of the carboxylato ligand. The six-coordinate cyclic
carbene complexes [Ru(κ2-O2CR1){dC(CH2Ph)OC(O)R2}(PiPr3)2]BArf [R1 ) R2 ) CHF2 (7a ),
CF3 (7b); R1 ) CF3, R2 ) H (7c)] were obtained on protonation of the precursors [Ru(κ1-
O2CR1)(κ2-O2CR2)(dCdCHPh)(PiPr3)2] (4a -c) with [H(OEt2)2]BArf. Both 7a and 7b undergo
a fluxional process in solution resulting in a κ1/κ2 interconversion of the carboxylato groups.
The crystal and molecular structures of 2b, 5e, and 6a were determined by X-ray
crystallography.
In tr od u ction
the presence of a donor solvent S, yields the six-
coordinate ruthenium carbynes [RuHCl(tCCH3)(PCy3)2-
(S)]A (S ) Et2O, H2O, PhNMe2) instead of the antici-
pated five-coordinate ruthenium vinylidenes [RuCl-
(dCdCH2)(PCy3)2(S)]A.5 These cationic ruthenium car-
bynes turned out to be highly efficient catalysts for
In the last two decades, transition-metal complexes
containing carbynes as ligands have received a great
deal of attention not only because of their unusual type
of bonding but also due to their growing application in
organic synthesis and alkyne metathesis.1 After Fischer
et al. reported in 1973 the preparation and structural
characterization of the first representatives of metal
carbynes,2 various synthetic routes to compounds with
a metal-carbon triple bond have been developed which
include the conversion of coordinated carbenes, vi-
nylidenes, allenylidenes, and even alkynyls to corre-
sponding CR units.3,4
(3) (a) Gallop, M. A.; Roper, W. R. Adv. Organomet. Chem. 1986,
25, 121-198. (b) Kim, H. P.; Angelici, R. J . Adv. Organomet. Chem.
1987, 27, 51-111. (c) Buhro, W. E.; Chisholm, M. H. Adv. Organomet.
Chem. 1987, 27, 311-369. (d) Fischer, H.; Hofmann, P.; Kreissl, F.
R.; Schrock, R. R.; Schubert, U.; Weiss, K. Carbyne Complexes; VCH:
Weinheim, Germany, 1988. (e) Mayr, A.; Hoffmeister, H. Adv. Orga-
nomet. Chem. 1991, 32, 227-324. (f) Engel, P. F.; Pfeffer, M. Chem.
Rev. 1995, 95, 2281-2309. (g) Hill, A. F. In Comprehensive Organo-
metallic Chemistry II; Abel, E. W., Stone, F. G. A., Wilkinson, G., Eds.;
Pergamon Press: Oxford, U.K., 1995; Vol. 7.
We have recently shown that the reaction of the
vinylidene(hydrido) complex [RuHCl(dCdCH2)(PCy3)2]
with acids HA having a noncoordinating anion A-, in
(4) Recent reports: (a) Luecke, H. F.; Bergman, R. G. J . Am. Chem.
Soc. 1998, 120, 11008-11009. (b) Baker, L. J .; Clark, G. R.; Rickard,
C. E. F.; Roper, W. R.; Woodgate, S. D.; Wright, L. J . J . Organomet.
Chem. 1998, 551, 247-259. (c) Tang, Y.; Sun, J .; Chen, J . Organome-
tallics 1999, 18, 2459-2465. (d) Zhang, L.; Gamasa, M. P.; Gimeno,
J .; Carbajo, R. J .; Lo´pez-Ortiz, F.; Guedes da Silva, M. F. C.; Pombeiro,
A. J . L. Eur. J . Inorg. Chem. 2000, 341-350. (e) Bannwart, E.;
J acobsen, H.; Furno, F.; Berke, H. Organometallics 2000, 19, 3605-
3619. (f) Furno, F.; Fox, T.; Schmalle, H. W.; Berke, H. Organometallics
2000, 19, 3620-3630. (g) Wen, T. B.; Yang, S.-Y.; Zhou, Z. Y.; Lin, Z.;
Lau, C.-P.; J ia, G. Organometallics 2000, 19, 3757-3761. (h) Wen, T.
B.; Cheung, Y. K.; Yao, J .; Wong, W.-T.; Zhou, Z. Y.; J ia, G. Organo-
metallics 2000, 19, 3803-3809.
† Dedicated to Professor Akio Yamamoto on the occasion of his 70th
birthday.
(1) (a) Yamamoto, A. Organotransition Metal Chemistry, Wiley: New
York, 1986; Chapter 6.3. (b) Collman, J . P.; Hegedus, L. S.; Norton, J .
R.; Finke, R. G. Principles and Application of Organotransition Metal
Chemistry, University Science Books: Mill Valley, CA, 1987; Chapter
6. (c) Elschenbroich, C.; Salzer, A. Organometallics; VCH: Weinheim,
Germany, 1992, Chapter 17.
(2) Fischer, E. O.; Kreis, G.; Kreiter, C. G.; Mu¨ller, J .; Huttner, G.;
Lorenz, H. Angew. Chem. 1973, 85, 618-620; Angew. Chem., Int. Ed.
Engl. 1973, 12, 564-566.
(5) Stu¨er, W.; Wolf, J .; Werner, H.; Schwab, P.; Schulz, M. Angew.
Chem. 1998, 110, 3603-3606; Angew. Chem., Int. Ed. 1998, 37, 3421-
3423.
10.1021/om010422x CCC: $20.00 © 2001 American Chemical Society
Publication on Web 07/19/2001

Carbene and Carbyne Ruthenium Complexes
Organometallics, Vol. 20, No. 17, 2001 3673
Sch em e 1
[H(OEt2)2]BArf. However, due to the almost instanta-
neous formation of the cationic carbyne complexes even
at low temperatures, these experiments failed. We note
that although [H(OEt2)2]BArf has been used as the acid
for protonation, the isolated products 2a -d do not
contain an ether molecule, which is in contrast to the
related cationic carbynes [RuHCl(tCCH3)(PCy3)2(S)]+,
where a solvent molecule is coordinated to attain the
coordination number six for ruthenium(II).
The formation of 2a -d is reversible. The cationic
carbyne complexes are readily deprotonated even by
weak bases such as NEt3 to give the parent metal
vinylidenes. Moreover, donor solvents such as acetone,
THF, or alcohols also deprotonate 2a -d to regenerate
1a -d . Owing to this behavior, we were unable to carry
out detailed studies about the reactivity of 2a -d and
could not prepare new ruthenium carbenes by reaction
of the cationic ruthenium carbynes with nucleophiles.
The composition and configuration of complexes 2a -d
were confirmed not only by elemental analyses but also
by NMR spectroscopy and the X-ray crystal structure
olefin metathesis, including the cross-olefin metathesis
of cyclopentene with methylacrylate to afford multiply
unsaturated esters CH2(C5H8)nCHCO2Me (n ) 1-3).
The cations [RuHCl(tCCH3)(PCy3)2(S)]+, however, are
rather labile and decompose in solution within 20 min
at room temperature. For this reason, we set out to
prepare more stable ruthenium carbynes in particular
by using different ruthenium vinylidenes as precursors.
In this paper we report the synthesis of five-coordi-
nate ruthenium carbyne complexes of the general
composition [RuCl2(tCCH2R)L2]BArf (BArf- ) [B{C6H3-
(CF3)2-3,5}4]-) as well as a detailed study on the
protonation of a series of vinylideneruthenium com-
pounds containing carboxylato ligands. This work led
to the observation of an equilibrium between isomeric
carbene and carbyne metal complexes for which there
is no precedence. Some preliminary results have already
been communicated.6
1
analysis of 2b. The H NMR spectra (in CDCl3) of the
cationic carbynes display a characteristic triplet at δ 4.5
(R ) Ph) or 3.3 (R ) tBu), which is assigned to the two
protons of the CH2R group. The 13C NMR spectra of
2a -d show the resonance of the CR atom of the carbyne
ligand as a triplet at δ 310 (R ) Ph) or 317 (R ) tBu)
and the signal of the CH2 carbon atom as a singlet at δ
62 (R ) Ph) or 72 (R ) tBu), respectively.
Complex 2b crystallizes with two formula units and
one molecule of dichloromethane in the asymmetric
unit. The structure of one of the two independent cations
is shown in Figure 1. The coordination geometry around
the ruthenium center is distorted square-pyramidal
with the carbyne carbon atom at the apical and the
phosphorus and chloro atoms at the basal positions. The
axes P1-Ru1-P2 and Cl1-Ru1-Cl2 are significantly
bent and pointing away from the Ru1-C1 unit. The
coordination geometry is nearly identical to that of the
parent vinylidene complex 1b, the only noticeable
difference being the more pronounced bending of the
P1-Ru1-P2 axis in 2b than in 1b [169.17(3)°].7a The
most remarkable feature of the structure, however, is
the distance Ru1-C1 [ca. 1.66 Å], which is among the
shortest metal-carbon bond lengths found for transi-
tion-metal carbynes.3,9 Only a few compounds contain-
ing a CrtCR or MntCR bond possess metal-carbon
distances slightly below 1.70 Å, while the Os-C dis-
tances found in osmium carbyne complexes lie in the
range 1.71-1.78 Å.4b,g,10
Resu lts a n d Discu ssion
Ca tion ic Ca r byn e Com p lexes w ith [Ru Cl2(P R3)2]
a s a Molecu la r Un it. The ruthenium vinylidenes 1a -
d 7 were readily protonated with [H(OEt2)2]BArf in
dichloromethane to give the five-coordinate, cationic
carbyne complexes 2a -d in almost quantitative yields
(Scheme 1). The products were isolated as pale yellow
or beige, moderately air-stable solids by precipitation
with pentane. Although the protonation could also be
carried out with CF3SO3H or HBF4, the BArf salts were
easier to handle and obtained solvent-free in analyti-
cally pure form. While solutions of 2a and 2b (R ) Ph)
in chloroform (if rigorously dried) are stable for days at
room temperature, solutions of 2c and 2d (R ) tBu) in
-
CHCl3 decompose in less than 24 h to give [HL]+BArf
(L ) PCy3 or PiPr3) and some unidentified ruthenium-
containing species. Compound 2d must be prepared at
low temperature due to its reduced stability.
Ca ta lytic Activity of 2a -d in Olefin Meta th esis.
The carbyne complexes 2a and 2b are good catalyst
Since it is known that in some cases the reaction of
vinylidene transition-metal complexes with strong acids
proceeds via the initial protonation at the metal center
and the generation of a hydridometal species as an
intermediate,8 we also attempted to detect such a
hydrido(vinylidene)ruthenium(II) cation [RuHCl2(dCd
CHR)(PR3)2]+ in the course of the reaction of 1a -d with
(8) (a) Ho¨hn, A.; Werner, H. Angew. Chem. 1986, 98, 745-746;
Angew. Chem., Int. Ed. Engl. 1986, 25, 737-738. (b) Ho¨hn, A.; Werner,
H. J . Organomet. Chem. 1990, 382, 255-272. (c) Carvalho, M. F. N.
N.; Henderson, R. A.; Pombeiro, A. J . L.; Richards, R. L. J . Chem. Soc.,
Chem. Commun. 1989, 1796-1797.
(9) Cambridge Structural Database, October 1999 Release. Allen,
F. H.; Kennard, O. Chem. Des. Automation News 1993, 8, 31.
(10) (a) La Pointe, A. M.; Schrock, R. R. Organometallics 1993, 12,
3379-3381. (b) Hodges, L. M.; Sabat, M.; Harman, W. D. Inorg. Chem.
1993, 32, 371-372. (c) Espuelas, J .; Esteruelas, M. A.; Lahoz, F. J .;
Oro, L. A.; Ruiz, N. J . Am. Chem. Soc. 1993, 115, 4683-4689. (d)
Weber, B.; Steinert, P.; Windmu¨ller, B.; Wolf, J .; Werner, H. J . Chem.
Soc., Chem. Commun. 1994, 2595-2596. (e) Esteruelas, M. A.; Lo´pez,
A. M.; Ruiz, N.; Tolosa, J . I. Organometallics 1997, 16, 4657-4667. (f)
Crochet, P.; Esteruelas, M. A.; Lo´pez, A. M.; Mart´ınez, M. P.; Oliva´n,
M.; On˜ate, E.; Ruiz, N. Organometallics 1998, 17, 4500-4509.
(6) Gonza´lez-Herrero, P.; Weberndo¨rfer, B.; Ilg, K.; Wolf, J .; Werner,
H. Angew. Chem. 2000, 112, 3392-3395; Angew. Chem., Int. Ed. 2000,
39, 3266-3269.
(7) (a) Katayama, H.; Ozawa, F. Organometallics 1998, 17, 5190-
5196. (b) Wolf, J .; W. Stu¨er, W.; Gru¨nwald, C.; Gevert, O.; Laubender,
M.; Werner, H. Eur. J . Inorg. Chem. 1998, 1827-1834.

3674 Organometallics, Vol. 20, No. 17, 2001
Gonza´lez-Herrero et al.
formed exclusively from 1b and an excess of RCO2Na
in THF. In contrast, the synthesis of compounds with
-
the fluorinated carboxylates CH3-nFnCO2 (n ) 1-3)
requires the use of the corresponding thallium salts.
While the complete conversion of 1b to 3c occurs by
stirring a solution of equimolar amounts of the dichloro
complex, CH2FCO2Na, and CF3SO3Tl in THF for 5 days,
treatment of 1b with an excess of CH2FCO2Na leads,
even after 12 days, only to partial conversion of 1b to
3c. Similar results were obtained if solutions of 1b
were treated with an excess of either CHF2CO2Na or
CF3CO2Na in THF; in the latter case, a mixture of the
mono- and the bis(carboxylato) complexes 3e and 4b
was isolated together with some unreacted starting
material.
The best method to prepare compounds 3d and
3e consists of the slow addition of a solution of
CHF2CO2Tl or CF3CO2Tl in THF to a solution of 1b in
the same solvent. Under these conditions, the excess of
the carboxylate in solution is minimized, and thus the
formation of the disubstituted derivatives 4a and 4b
occurs only to a small extent. Complex 3f has been
obtained by using 1 equiv of PhCO2H in the presence
of Et3N, while compounds 3g-j containing substituted
benzoates as ligands are prepared from 1b and an
excess of the corresponding sodium carboxylate in THF.
The disubstituted complexes 4a and 4b are formed in
ca. 80-85% yield upon treatment of 1b with 2.5 equiv
of CHF2CO2Tl or CF3CO2Tl, respectively, whereas the
mixed bis(carboxylate) 4c is generated by ligand ex-
change from 4b and excess HCO2Na.
F igu r e 1. Molecular structure (ORTEP diagram) of one
of the two independent cations of 2b‚1/2CH2Cl2. Selected
bond distances (Å) and angles (deg) with estimated stan-
dard deviations: Ru-C1 1.660(5), Ru-Cl1 2.3288(14),
Ru-Cl2; 2.3218(14), Ru-P2 2.4749(17), Ru-P1 2.4541(16),
C1-C2 1.481(7); C1-Ru-Cl2 100.98(17), C1-Ru-Cl1
101.58(17), Cl2-Ru-Cl1 157.44(6), C1-Ru-P1 97.17(16),
Cl2-Ru-P1 88.25(5), Cl1-Ru-P1 88.77(5), C1-Ru-P2
102.26(16), Cl2-Ru-P2 85.69(5), Cl1-Ru-P2 89.73(5),
P1-Ru-P2 160.42(5), C2-C1-Ru 176.9(4), C1-C2-C3
113.2(4).
Sch em e 2
Evidence for the chelating coordination of the respec-
tive RCO2- ligand in the monocarboxylato complexes is
provided by the IR spectra of 3a -d , 3f, and 3g, which
display an absorption of medium intensity at around
1580-1520 cm-1. This is assigned, according to refer-
ence data,11 to the asymmetric ν(OCO) stretching fre-
quency. While a corresponding absorption could not be
observed in the IR spectra (in Nujol) of 4a and 4b, the
presence of a unidentate carboxylato ligand in these
compounds is indicated by the appearance of a νas(OCO)
band at 1691 and 1701 cm-1, respectively. The IR
spectrum of the mixed complex 4c shows an absorption
at 1701 cm-1 arising from the unidentate trifluoroac-
etato and a second one at 1550 cm-1 arising from the
chelating formato ligand. With regard to the NMR data,
the most characteristic feature is the low-field signal
for the CR carbon atom of the vinylidene ligand in the
13C NMR spectra at δ ca. 350 for 3a -j and at δ ca. 360
for 4a -c, which is in good agreement with the chemical
shifts observed for other mononuclear vinylideneruthe-
nium complexes.7,12
precursors for the ring-opening metathesis polymeriza-
tion (ROMP) of cyclooctene. Solutions of cyclooctene and
compounds 2a or 2b (1 mol %, 10 mM) in CH2Cl2
became viscous within ca. 6 h at 20 °C, and the complete
consumption of the monomer took place after 20 h.
During the catalysis, the only detectable ruthenium-
containing species is the carbyne complex 2a or 2b, the
concentration of which decreases only slightly after 6
h. The phosphonium salt [HL]+BArf (L ) PiPr3 or
-
PCy3) can also be detected by NMR. This finding
suggests that the formation of the catalytically active
compound involves the elimination of one of the phos-
phine ligands of 2a ,b and that the 14-electron vinylidene
complex, depicted in Scheme 2, is the real catalyst in
the observed ROMP of cyclooctene. Compounds 2c and
2d exhibit a significantly lower catalytic activity in this
process, which could be due to their reduced stability.
Six-Coor d in a te Vin ylid en er u th en iu m Com -
p ou n d s w ith Ca r boxyla to Liga n d s. The preparation
of a series of vinylideneruthenium(II) complexes con-
taining carboxylato ligands was achieved by treatment
of the starting material 1b with RCO2M, where M is
Na, Tl, or Et3NH, respectively (Scheme 3). However,
both the conditions required for these reactions and the
composition of the products significantly depend on the
nature of the carboxylate.
To confirm the coordination mode of the carboxylato
ligands in compounds 4a and 4b, a variable-tempera-
ture (VT) 19F NMR study has been carried out. The
results illustrate not only that these complexes are
(11) (a) Robinson, S. D.; Uttley, M. F. J . Chem. Soc., Dalton Trans.
1973, 1912-1920. (b) Nakamoto, N. Infrared and Raman Spectra of
Inorganic and Coordination Compounds, 3rd ed.; Wiley: New York,
1978.
(12) (a) Bruce, M. I.; Swincer, A. G. Adv. Organomet. Chem. 1983,
22, 59-128. (b) Bruce, M. I. Chem. Rev. 1991, 91, 197-257. (c) Werner,
H.; Stark, A.; Schulz, M.; Wolf, J . Organometallics 1992, 11, 1126-
1130. (d) Werner, H.; Stark, A.; Steinert, P.; Gru¨nwald, C.; Wolf, J .
Chem. Ber. 1995, 128 (8), 49-62. (e) Martin, M.; Gevert, O.; Werner,
H. J . Chem. Soc., Dalton Trans. 1996, 2275-2283.
The monosubstituted derivatives 3a and 3b with the
relatively electron-rich formato and acetato ligands are

Carbene and Carbyne Ruthenium Complexes
Organometallics, Vol. 20, No. 17, 2001 3675
Sch em e 3a
a
L ) PiPr3.
Sch em e 4a
a
L ) PiPr3.
-
indeed six-coordinate with one unidentate and one
bidentate carboxylate but also that in solution an
interchange of the bonding mode between the two
RCO2- units occurs. Thus, at 190 K, the 19F{1H} NMR
spectrum of 4a in CD2Cl2 displays two singlets at δ
-123.2 and -126.1, which coalesce at 215 K and give
rise at 293 K to one resonance at δ -124.5. Similarly,
in the 19F NMR spectrum of 4b in CD2Cl2 at 180 K two
broad singlets of equal intensity appear at δ -74.14 and
-74.63, which coalesce at 200 K and give rise at 290 K
to one singlet resonance at δ -74.75. By using the
Eyring equation,13 approximate values of ∆Gq ) 9.1 (4a )
and 8.9 (4b) kcal mol-1 were calculated for the free
activation energy of these exchange processes at the
coalescence temperature. In contrast, analogous VT
NMR measurements revealed that the mixed complex
4c, containing one chelating formato and one monoden-
tate trifluoroacetato ligand, is not fluxional in solution,
probably due to the more favorable coordination ability
of the formato compared to the trifluoroacetato moiety.
The formato compounds 3a and 4c undergo a decarb-
oxylation reaction leading to the hydrido(vinylidene)-
ruthenium derivatives [RuHCl(dCdCHPh)(PiPr3)2] and
[RuH(κ2-O2CCF3)(dCdCHPh)(PiPr3)2], which have been
the HCO2 unit is achieved within 9 h (for 3a ) and 28
h (for 4c), respectively. The generation of the hydrido-
(vinylidene) compounds is always accompanied by the
formation of small amounts of byproducts which could
not be exactly identified.
Ca r byn e a n d Ca r ben e Ru th en iu m Com p lexes
fr om Ca r boxyla to(vin ylid en e) P r ecu r sor s. Simi-
larly as described for the formation of 2a -d (see Scheme
1), the reaction of the carboxylato compounds 3a -j with
[H(OEt2)2]BArf affords cationic complexes, which can be
isolated as the BArf salts in good to excellent yields.
While the analytical composition of these ionic products
corresponds in all cases to that of an 1:1 adduct of the
parent ruthenium vinylidene 3a -j and HBArf, their
nature depends quite remarkably on the basicity of the
carboxylato ligand.
P r oton a tion of [Ru Cl(K2-O2CR)(dCdCHP h )-
(P iP r 3)2], w h er e R ) H, CH3, C6H5. The protonation
of compounds 3a , 3b, and 3f containing the relatively
electron-rich formato, acetato, or benzoato ligand leads
to the formation of the cyclic carbene complexes 6a , 6b,
and 6f, which are the result of a nucleophilic attack of
the carboxylato ligand to the CR carbon atom of the
initially generated ruthenium carbynes 5a , 5b, and 5f,
respectively (Scheme 4). For R ) H, CH3, and C6H5,
these carbyne derivatives could not be detected by
spectroscopic means.
1
identified by their H NMR spectra.7b,14 The elimination
of CO2 takes place even at room temperature with the
consequence that solutions of 3a and 4c always contain
small amounts of the corresponding hydrido complex.
If solutions of 3a or 4c in toluene containing 2 equiv of
PiPr3 are stirred at 60 °C, complete decarboxylation of
The fact that the protonation takes place at the Câ
carbon atom of the vinylidene ligand was confirmed by
the H and 13C NMR data of 6a , 6b, and 6f. In the H
NMR spectra, the resonance of the CH2Ph protons
appears as a somewhat broadened singlet (the broaden-
ing probably being due to unresolved coupling with the
1
1
(13) Friebolin, F. Ein- und Zweidimensionale NMR-Spektroskopie;
VCH: Weinheim, Germany, 1988.
(14) J ung, S. Dissertation, University of Wu¨rzburg, in preparation.

3676 Organometallics, Vol. 20, No. 17, 2001
Gonza´lez-Herrero et al.
Sch em e 5a
a
L ) PiPr3.
carbenes containing a RudC(OR)R′ moiety.9 The plane
of the chelate ring formed by Ru, C1, O2, C9, and O1
(main deviation from planarity 0.017 Å) lies essentially
perpendicular to the plane containing the ruthenium
and phosphorus atoms, which probably minimizes the
steric repulsion between the ring atoms and the isopro-
pyl groups.
Regarding the rather long C1-O2 distance of
1.453(7) Å, we assume that the pπ(O)fpπ(C) bond
component usually present in alkoxycarbene metal
complexes is strongly reduced in 6a and that the
C1-O2 bond is relatively weak. This interpretation is
supported by the short Ru-C1 distance, which reflects
some carbyne character for the metal-to-carbon bond.
Therefore, for an adequate description of the bonding
in 6a , also the resonance form 6a ′ should be considered
as indicated in Scheme 5. This resonance form would
represent an intermediate stage between a five-mem-
bered chelate ring and a separated Ru(κ1-O2CH)-
(tCCH2Ph) unit. We note in this context that the
distances C9-O2 of 1.309(8) Å and C9-O1 of 1.211(8)
Å in 6a are slightly shorter or longer, respectively, than
the average C-O and CdO distances in carboxylic
esters (1.336 and 1.196 Å).17
The formation of Fischer-type carbene complexes via
attack of a nucleophile on a metal-bonded carbyne is a
well-established reaction.3,18 The conversion of the Ru-
(κ2-O2CR)(tCR′) fragment into the cyclic carbene Ru-
{dC(R′)OC(O)R}, which occurs during the formation of
6a , 6b, and 6f, represents a particular variant of this
reaction with the nucleophile being already present in
the starting material. However, to the best of our
knowledge, this kind of rearrangement had not been
observed before. Recently, Esteruelas et al. reported that
the related carbyneosmium complexes [OsH(κ2-O2CCH3)-
(tCR)(PiPr3)2]BF4, with R ) CHdC(CH3)2, CH2tBu, and
CH3, are kinetically stable and do not rearrange to a
cyclic osmium carbene.19 There exist some similarities,
however, between 6a , 6b, and 6f and the compounds
[(η5-C5H5)Ru{C(dCHCO2CH3)OC(O)CH3}(PPh3)],20 [Ru-
{C(dCHPh)OC(O)CH3}(CO)(acetone)(PiPr3)2]BF4,21 and
[RuCl{C(dCHPh)OC(O)CH2CH3}(CO)(PPh3)2],22 which
all contain a five-membered Ru-C-O-C-O ring gen-
erated by nucleophilic attack of a metal-bonded carb-
oxylate to the CR carbon atom of a vinylidene ligand.
F igu r e 2. Molecular structure (ORTEP diagram) of the
cation of 6a . Selected bond distances (Å) and angles (deg)
with estimated standard deviations: Ru-C1 1.787(7), Ru-
Cl 2.3306(17), Ru-O1 2.108(4), Ru-P1 2.4291(19), Ru-
P2 2.4569(19), O1-C9 1.211(8), O2-C9 1.309(8), C1-O2
1.453(7), C1-C2 1.521(10); C1-Ru-O1 79.6(2), C1-Ru-
Cl 105.5(2), C1-Ru-P1 97.2(2), C1-Ru-P2 103.4(2), Cl-
Ru-O1 174.93(14), P1-Ru-P2 159.11(6), Cl-Ru-P1 88.36-
(6), Cl-Ru-P2 89.55(6), O1-Ru-P1 91.42(12), O1-Ru-
P2 88.85(12), Ru-C1-C2 135.6(5), Ru-C1-O2 117.0(5),
C2-C1-O2 107.2(6), C1-O2-C9 111.2(5), O1-C9-O2
122.3(6), Ru-O1-C9 109.9(4), C1-C2-C3 117.1(6).
31P nuclei) at δ ca. 5.0, which is about 0.5 ppm downfield
compared with the carbyne complexes 2a and 2b.
Moreover, the signal of the HCO2 proton of 6a is a
singlet and not a triplet, as was observed in the case of
the parent vinylidene compound 3a . The 13C NMR
spectra of 6a , 6b, and 6f display a triplet at about δ
287, which is typical for a metal-coordinated carbene.
Another typical feature is that the solid-state IR spectra
of 6a , 6b, and 6f do not show any bands assignable to
a chelating carboxylato ligand.
The single-crystal X-ray structure analysis of 6a
(Figure 2) confirmed the formation of a metal carbene.
The coordination geometry around the ruthenium center
is distorted square-pyramidal with the carbene carbon
at the apical position and the chlorine, the oxygen, and
the two phosphorus atoms at the basal positions. In
contrast to the Cl-Ru-O1 axis, which is almost linear,
the P1-Ru-P2 axis is significantly bent, both phos-
phorus atoms pointing away from the Ru-C1 unit. An
analogous square-pyramidal configuration has been
found for the carbeneruthenium complexes [RuCl2-
(dCHCH2Ph)(PiPr3)2]15 and [RuCl2(dCHR)(PCy3)2] (R
) 4-C6H4Cl, CHdCPh2)16 as well as for the related
vinylidene derivatives [RuCl2(dCdCHPh)L2] (L ) PiPr3,
PCy3).7 Compared with [RuCl2(dCHCH2Ph)(PiPr3)2]
and [RuCl2(dCHR)(PCy3)2], the bond length Ru-C1 in
6a is rather short, whereas the distance C1-O2 is ca.
0.07-0.15 Å longer than in Fischer-type ruthenium
(17) Allen, F. H.; Kennard, O.; Watson, D. G.; Brammer, L.; Orpen,
A. G.; Taylor, R. J . Chem. Soc., Perkin Trans. 2 1987, S1-S19.
(18) K. H. Do¨tz, H. Fischer, P. Hofmann, F. R. Kreissl, U. Schubert,
K. Weiss, Transition Metal Carbene Complexes; VCH: Weinheim,
Germany, 1983.
(19) Buil, M. L.; Eisenstein, O.; Esteruelas, M. A.; Garc´ıa-Yebra,
C.; Gutie´rrez-Puebla, E.; Oliva´n, M.; On˜ate, E.; Ruiz, N.; Tajada, M.
A. Organometallics 1999, 18, 4949-4959.
(20) Daniel, T.; Mahr, N.; Braun, T.; Werner, H. Organometallics
1993, 12, 1475-1477.
(15) Gru¨nwald, C.; Gevert, O.; Wolf, J .; Gonza´lez-Herrero, P.;
Werner, H. Organometallics 1996, 15, 1960-1962.
(16) (a) Schwab, P.; Grubbs, R. H.; Ziller, J . W. J . Am. Chem. Soc.
1996, 118, 100-110. (b) Nguyen, S. T.; Grubbs, R. H.; Ziller, J . W. J .
Am. Chem. Soc. 1993, 115, 9858-9859.
(21) Esteruelas, M. A.; Lahoz, F. J .; Lo´pez, A. M.; On˜ate, E.; Oro,
L. A. Organometallics 1994, 13, 1669-1678.
(22) Kawano, H.; Masaki, Y.; Matsunaga, T.; Hiraki, K.; Onishi, M.;
Tsubomura, T. J . Organomet. Chem. 2000, 601, 69-77.

Carbene and Carbyne Ruthenium Complexes
Organometallics, Vol. 20, No. 17, 2001 3677
F igu r e 3. Variable-temperature 1H (resonance of the CH2Ph protons), 31P, and 19F NMR spectra for the equilibrium
between 5e and 6e.
Sch em e 6a
a
L ) PiPr3.
Since also in these compounds relatively short Ru-CR
and relatively long CR-O bond distances have been
encountered, it has been assumed that the Ru{C-
(dCHR)OC(O)R′} unit represents an intermediate stage
between a five-membered chelate ring and a Ru(κ1-
O2CR)(dCdCHR′) fragment, the carbonyl group of the
carboxylato ligand being en route to nucleophilic attack
to the CR vinylidene carbon atom. The complex [RuCl-
{dC(CH2Ph)OC(O)CH3}(CO)(PiPr3)2]BF4 with the same
carbene ligand as in 6b had previously been described
but was not structurally characterized.21
P r oton ation of Vin yliden er u th en iu m Com pou n ds
Con ta in in g Electr on -P oor Ca r boxyla to Liga n d s.
Following the observation that the interaction of the
formato ligand with the CR carbon atom in 6a is
relatively weak, we wondered what the behavior of the
starting materials containing a carboxylato ligand with
an electron-withdrawing substituent R toward [H(OEt2)2]-
BArf is. We took into consideration that those substi-
tuents could disfavor the nucleophilic attack at the
RutC unit and could thus allow the isolation (or at least
the spectroscopic characterization) of six-coordinate
carbyneruthenium complexes.
1:2. The comparison of the chemical shifts of these
signals with those of the CH2 protons of the metal
carbynes 2a and 2b on one side and the metal carbenes
6a , 6b, and 6f on the other allows us to assign the more
intense resonance at δ 4.59 to the carbyne 5e and the
other at δ 5.20 to the carbene 6e. These two signals
coalesce at 225 K and, by raising the temperature to
290 K, give rise to a singlet at δ 4.88. The 19F NMR
spectrum displays at 190 K two sharp singlets at δ
-72.9 and -75.1, which correspond to the fluorine
atoms of the CF3 group of 6e and 5e, respectively. These
signals coalesce at 230 K and at 290 K give rise to one
singlet resonance at δ -73.9. Similarly, the 31P NMR
spectrum shows at 200 K two singlets at δ 61.7 (5e) and
50.8 (6e), which coalesce at 250 K and at 290 K exhibit
a broad signal at δ 56.7.
1
In the same way as described for 5e/6e, VT H, 31P,
and, if possible, 19F NMR measurements established the
existence of equilibria between the respective carbene
and carbyne complexes containing carboxylato ligands
-
RCO2 with CH2F, CHF2, C6F5, or various substituted
phenyl groups R. Well below the coalescence tempera-
ture, in the 1H NMR spectra the resonances for the
CH2Ph protons appear (in CD2Cl2) invariably in a very
narrow range at around δ 4.5 for the carbyne complexes
5 and at around δ 5.0 for the cyclic carbenes 6. This
result allowed in all cases the unequivocal identification
of the isomers 5 and 6. The complete set of 13C NMR
data could be obtained for the major isomers 6c, 5d ,
and 6g-i as well as for both 5j and 6j at low temper-
atures (see Experimental Section). In these spectra, the
resonance for the carbene carbon atom always appears
as a triplet between δ 284.4 and 286.8, and that is at
almost the same chemical shift as found for the isolated
The protonation of compounds 3c-e and 3g-j, which
all contain a relatively electron-poor carboxylato ligand,
furnishes always an equilibrium between the respective
carbyne 5 and the isomeric, cyclic carbene 6 (see Scheme
6). The existence of this equilibrium was established by
1
VT NMR measurements. As an example, the H, 31P,
and 19F NMR spectra of the product obtained by
protonation of 3e (R ) CF3) with [H(OEt2)2]BArf in
CD2Cl2 at different temperatures are shown in Figure
1
3. At 190 K, the H NMR spectrum displays two broad
signals at δ 5.20 and 4.59 in the approximate ratio of

3678 Organometallics, Vol. 20, No. 17, 2001
Gonza´lez-Herrero et al.
Ta ble 1. P a r a m eter s for th e Equ ilibr ia betw een
th e Ca r byn e Com p lexes 5 a n d th e Isom er ic Cyclic
Ca r ben es 6a
pKa of
RCO2H
R
x5
x6
Tc ∆Gq
∆Gq
∆G0
6f5
5f6
a
b
c
d
e
f
H
3.75
4.76
2.59
1.34
0.23
4.19
0
0
1.00
1.00
CH3
CH2F
CHF2
CF3
0.10 0.90 280 13.1
0.88 0.12 240 12.0
0.65 0.35 225 10.6
14.3
11.1 -0.9
10.3 -0.3
1.2
C6H5
0
1.00
g
h
i
C6H4NO2-4
C6H4NO2-2
C6F5
3.41 <0.05 >0.95
2.16 <0.05 >0.95
1.52
0.05 0.95 270 12.4
0.35 0.65 270 12.5
14.0
12.8
1.6
0.3
j
C6H3(NO2)2-2,4 1.42
a
x denotes the relative concentration of the complexes 5 and
6; Tc in K; ∆G in kcal mol-1
.
F igu r e 4. Relative concentration of the cyclic carbene 6
(x6) versus pKa of RCO2H.
ruthenium carbenes 6a , 6b, and 6f. In contrast, the
signal for the carbyne carbon atom of 5d and 5j is
observed at δ 330.0 and 330.8, respectively. It should
be mentioned that the complete set of 13C NMR data
for compounds 5e and 6e could not be obtained because
at the temperature required for the decoalescence of the
respective signals (below 243 K) the carbyne complex
5e already precipitates from the solution.
stronger Ru-O and C-O bonds, which is in agreement
with the expected tendency. However, the relative
amount of 5 and 6 indicates that with increasing
basicity of the anion CH3-nFnCO2- the formation of the
cyclic carbene with one Ru-O and one C-O bond is
favored to a greater extent than that of the carbyne with
two Ru-O bonds. The only deviation from this tendency
is found for the equilibrium 5d /6d (R ) CHF2), for which
we have no explanation. With regard to the second
series (f-j), it appears that the substituted benzoates
form stronger Ru-O and C-O bonds than the fluori-
nated acetates having a comparable basicity and thus
prefer in all cases the formation of the cyclic carbene 6.
As anticipated, the isomers 5 and 6 differ in their free
energies and their relative amounts at the equilibrium.
The latter were determined by the integration of the
signals of the CH2 protons and, for the products with
-
the carboxylates CH3-nFnCO2 (n ) 1-3) as ligands,
also by integrating the corresponding resonances of the
fluorine atoms in the 19F NMR spectrum. The difference
in the free energy ∆G0 between the two isomers was
calculated by using the Boltzmann equation.13 More-
over, on the basis of the method reported by Shanan-
Atidi and Bar-Eli,23 the VT NMR measurements also
allowed the determination of the free energies of activa-
The product isolated as a solid is in most cases the
pure major isomer. Addition of pentane to a dichlo-
romethane solution containing both isomers leads to the
precipitation of the deeply colored carbene complexes
6c (orange), 6g (dark green), 6h , 6i (both dark violet),
and 6j (olive-green) and of the yellow carbyne 5e. For
R ) CHF2, an orange solid is obtained, which contains
both 5d and 6d according to the solid-state IR spectrum
(see Experimental Section). However, a pure sample of
yellow 5d has been obtained by slow crystallization from
a solution in dichloromethane at -78 °C.
The result of the X-ray crystal structure analysis of
5e is shown in Figure 5. The diagram reveals that the
ruthenium center possesses a distorted octahedral
coordination sphere with a significant bending of
the C1-Ru-O1 axis. Both the Cl1-Ru-O2 and
P1-Ru-P2 axes with the bond angles of, respec-
tively, 161.45(9)° and 169.94(4)° are bent away from
the Ru-C1 unit. The four-membered ring Ru-O1-
C70-O2 is exactly planar and lies almost perpendicular
to the P1-Ru1-P2 plane. However, the most notewor-
thy structural feature is that the trifluoroacetato ligand
is unsymmetrically coordinated. While the Ru-O2
distance [2.133(3) Å] corresponds to a Ru-O single
bond, the distance Ru-O1 [2.336(3) Å] is considerably
longer. Moreover, the small bite of the trifluoroacetato
ligand accounts for the O1-Ru-O2 angle of 58.56(11)°.
A similar coordination geometry for ruthenium and a
related bonding situation of the trifluoroacetato ligand
have been found in the enynylruthenium(II) compound
[Ru{C(dCHPh)(CtCPh)}(κ2-O2CCF3)(CO)(PPh3)2], where
the bond lengths Ru-O1 and Ru-O2 are 2.353 and
2.234 Å, respectively.24 The angle Ru-C1-C2 of
173.0(4)° is nearly linear, as expected for a sp-hybridized
tion ∆Gq
and ∆Gq
at the temperature of coales-
5f6
6f5
cence Tc. Table 1 summarizes the parameters for the
equilibria between the isomers 5 and 6. The pKa values
of the corresponding carboxylic acids RCO2H in aqueous
solution, which reflect the electron-withdrawing char-
acter of the group R, are also included in order to
provide a basis for the discussion of the observed
differences.
Figure 4 illustrates the relation between the basicity
of the carboxylato ligand and the relative amount of the
isomers 5 and 6. For the two equilibria 5g/6g and 5h /
6h , the concentration of the respective carbyne complex
was very low and, therefore, it was not possible to
determine with good accuracy both the ratio between
the two isomers and the temperature of coalescence.
To analyze the data shown in Table 1 and Figure 4,
it is convenient to consider two separate series of
compounds: that with the acetato (b-e) and that with
the benzoato ligands (f-j). For the first series with c-e,
the coalescence temperature and the activation energies
∆Gq
and ∆Gq
increase with the basicity of the
5f6
6f5
carboxylate CH3-nFnCO2-. This means that both the
chelating coordination of the substituted acetate and the
formation of the cyclic carbene are energetically more
favored if the basicity of the anionic ligand increases.
In other words, the more basic carboxylates form
(23) Shanan-Atidi, H.; Bar-Eli, K. H. J . Phys. Chem. 1970, 74, 961-
963.

Carbene and Carbyne Ruthenium Complexes
Organometallics, Vol. 20, No. 17, 2001 3679
of 7a -c show the signal of the CH2 protons at δ 5.07,
5.24, and 5.04, respectively, and that is at almost the
same chemical shift as found for the corresponding five-
coordinate carbene complexes 6d , 6e, and 6a , having
the same Ru{dC(CH2Ph)OC(O)R} unit. The 13C NMR
spectra of 7a -c display a low-field resonance at about
δ 295-331, which is assigned to the carbene carbon
atom and is thus in agreement with the proposed
structure.
A variable-temperature 19F NMR study revealed that
both 7a and 7b are fluxional in solution. The 19F{1H}
NMR spectrum of 7a shows at 200 K two singlets at δ
-123.7 and -125.4, which correspond to two different
difluoroacetate groups. By comparing these chemical
shifts with those of the CHF2CO2 group of the carbyne
5d (δ -126.7) and the carbene 6d (δ -123.0), it is
possible to assign the signal at δ -125.4 to the chelating
difluoroacetato ligand and that at δ -123.7 to the
difluoroacetate group generating the five-membered
ring. The two signals coalesce at 255 K, and by raising
the temperature to 290 K a somewhat broadened sing-
let is observed at δ -124.9. Similarly, the 19F{1H}
NMR spectrum of 7b displays at 180 K two singlets at
δ -74.3 for the Ru(κ2-O2CCF3) and at δ -72.5 for the
Ru,C-bonded CF3CO2 unit. These signals coalesce at 240
K and at 290 K give rise to a singlet at δ -73.4. Using
the Eyring equation,13 approximate values ∆Gq ) 11.2
(7a ) and 10.5 (7b) kcal mol-1 were calculated for the
activation energies of the exchange processes at the
coalescence temperature. Unlike 7a and 7b, complex 7c
is nonfluxional in solution.
As already discussed for compounds 2a -d , also the
formation of complexes 5/6 and 7 is reversible. The
carbene and carbyne metal cations react either with 1
equiv of NEt3 in dichloromethane or with a coordinating
solvent such as THF to regenerate the parent metal
vinylidenes. With the noteworthy exception of compound
6f (R ) Ph), which is stable in dichloromethane or
chloroform solution at room temperature for at least 24
h, all the other complexes of the series 5/6 decompose
within ca. 2 h to afford the salt [HPiPr3]BArf together
with some unidentified ruthenium-containing species.
We note that none of the carbene and carbyne complexes
of the series 5/6 and 7 are catalytically active in ROMP
of cyclooctene.
F igu r e 5. Molecular structure (ORTEP diagram) of the
cation of 5e. Selected bond distances (Å) and angles (deg)
with estimated standard deviations: Ru-C1 1.660(4),
Ru-Cl 2.3143(11), Ru-O1 2.336(3), Ru-O2 2.133(3),
Ru-P1 2.4823(11), Ru-P2 2.4922(11), C1-C2 1.489(6),
C2-C3 1.524(7), O1-C70 1.244(5), O2-C70 1.253(5);
C1-Ru-O1 154.74(16), C1-Ru-O2 96.18(16), C1-Ru-Cl
102.35(15), C1-Ru-P1 95.06(14), C1-Ru-P2 93.40(14),
O1-Ru-O2 58.56(11), O1-Ru-Cl 102.90(8), O1-Ru-P1
86.58(8), O1-Ru-P2 88.09(8), O2-Ru-Cl 161.45(9),
O2-Ru-P1 92.23(9), O2-Ru-P2 92.26(9), Cl-Ru-P1
85.23(4), Cl-Ru-P2 87.66(4), P1-Ru-P2 169.94(4),
Ru-C1-C2 173.0(4), C1-C2-C3 110.9(4), Ru-O1-C70
84.8(2), Ru-O2-C70 93.8(3), O1-C70-O2 122.9(4).
Sch em e 7a
a
L ) PiPr3.
Con clu sion s
carbyne carbon atom. We also note that the distance
Ru-C1 of 1.660(4) Å is almost identical to that of the
carbynedichloro complex 2b (see above).
The work presented in this paper has shown that, by
using [H(OEt2)2]BArf as the proton source, neutral five-
or six-coordinate vinylidene complexes of the general
composition [RuCl2(dCdCHR)(L)2] (2), [RuCl(κ2-O2CR)-
(dCdCHPh)(PiPr3)2] (3), and [Ru(κ1-O2CR1)(κ2-O2CR2)-
(dCdCHPh)(PiPr3)2] (4) can be protonated at the Câ
carbon atom of the vinylidene ligand. The observation
that in all cases the protonation is reversible and that
only very weak bases are needed to deprotonate the
cationic species illustrates the weak basic character of
the dCHR vinylidene unit.
The type of products resulting from the protonation
critically depends on the anionic ligands present in the
starting material. While the reaction of the dichloro
complexes 1 with [H(OEt2)2]BArf affords exclusively the
five-coordinate ruthenium carbynes [RuCl2(tCCH2R)-
L2]BArf (2), the protonation of the monocarboxylato
P r oton a tion of Vin ylid en er u th en iu m Com p lexes
Con ta in in g Tw o Ca r boxyla to Liga n d s. The proto-
nation of compounds 4a -c with [H(OEt2)2]BArf in
dichloromethane proceeds at low temperature to give
the six-coordinate carbene complexes 7a -c in 75-99%
yield (Scheme 7). They were isolated as pale yellow (7b)
or orange (7a , 7c) microcrystalline solids by precipita-
tion with pentane. The formation of 7c involves the
nucleophilic attack of the formato ligand to the CR
carbon atom of a metal carbyne intermediate and also
the change of coordination mode of the trifluoroacetato
1
ligand from mono- to bidentate. The H NMR spectra
(24) Dobson, A.; Moore, D. S.; Robinson, S. D.; Hursthouse, M. B.;
New, L. Polyhedron 1985, 4, 1119-1130.

3680 Organometallics, Vol. 20, No. 17, 2001
Gonza´lez-Herrero et al.
(vt, N ) 6.4 Hz, C2, C6 of C6H11), 25.8 (s, C4 of C6H11). 31P-
{1H} NMR (162.0 MHz, CDCl3): δ 55.4 (s).
derivatives 3 leads predominantly to an equilibrium
mixture of the six-coordinate carbyne complex [RuCl-
(κ2-O2CR)(tCCH2Ph)(PiPr3)2]BArf (5) and the isomeric
five-coordinate cyclic carbene [RuCl{)C(CH2Ph)OC-
(O)R}(PiPr3)2]BArf (6). The position of this equilibrium
depends on the basicity of the carboxylato ligand,
thereby the more basic carboxylates favoring the forma-
tion of the cyclic ruthenium carbene 6 versus the
isomeric ruthenium carbyne 5. The six-coordinate car-
bene complexes [Ru(κ2-O2CR){dC(CH2Ph)OC(O)R}-
(PiPr3)2]BArf (7a and 7b), obtained by protonation of
the corresponding biscarboxylato compounds 4a and 4b,
undergo a fluxional process in solution which leads to
an exchange of the bonding mode between the two
carboxylato ligands. This process is closely related to
the equilibrium reaction between 5 and 6, and in fact
the activation energies found for the dynamics of 7a and
7b are very similar to those of the equilibria 5d /6d and
5e/6e. The result that the protonation of the mixed
biscarboxylate 4c gives exclusively the chelate complex
[Ru(κ2-O2CCF3){dC(CH2Ph)OC(O)H}(PiPr3)2]BArf (7c),
in which the more basic formate forms the cyclic carbene
unit, is in agreement with the observed tendency.
P r ep a r a tion of [Ru Cl2(tCCH2P h )(P iP r 3)2]BAr f (2b).
This complex was prepared as described for 2a , starting from
1b (143 mg, 0.24 mmol) and [H(OEt2)2]BArf (243 mg, 0.24
mmol). Pale yellow solid: yield 331 mg (95%); mp 118 °C dec.
Anal. Calcd for C58H61BCl2F24P2Ru: C, 47.75; H, 4.21. Found:
1
C, 47.48; H, 4.02. H NMR (200 MHz, CDCl3): δ 7.71 (br m,
8H, ortho-H of Arf), 7.53 (br m, 4H, para-H of Arf), 7.40 (br m,
3H, C6H5), 7.16 (m, 2H, C6H5), 4.49 (t, 4J PH ) 2.7 Hz, 2H, CH2-
3
Ph), 3.06 (m, 6H, PCHCH3), 1.30 (dvt, N ) 15.7, J HH ) 7.3
Hz, 36H, PCHCH3). 13C{1H} NMR (50.3 MHz, CDCl3): δ 310.0
(t, 2J PC ) 5.1 Hz, RutC), 130.3, 130.2, 129.2, 125.9 (all s, C6H5),
62.4 (s, CH2Ph), 24.6 (vt, N ) 10.8 Hz, PCHCH3), 19.6 (s,
PCHCH3). 31P{1H} NMR (81.0 MHz, CDCl3): δ 62.6 (s).
P r ep a r a tion of [Ru Cl2(tCCH2tBu )(P Cy3)2]BAr f (2c).
This complex was prepared as described for 2a , starting from
1c (216 mg, 0.27 mmol) and [H(OEt2)2]BArf (268 mg, 0.27
mmol). Beige solid: yield 337 mg (96%); mp 132 °C dec. Anal.
Calcd for C74H89BCl2F24P2Ru: C, 52.93; H, 5.34. Found: C,
1
52.61; H, 5.06. H NMR (200 MHz, CDCl3): δ 7.73 (br m, 8H,
4
ortho-H of Arf), 7.56 (br m, 4H, para-H of Arf), 3.33 (t, J PH
)
3.3 Hz, 2H, CH2tBu), 2.88 (br, 6H, CH of C6H11), 2.18-1.42
(br m, 60H, CH2 of C6H11), 1.17 (s, 9H, CCH3). 13C{1H} NMR
2
(50.3 MHz, CDCl3): δ 317.0 (t, J PC ) 3.8 Hz, RutC), 72.3 (s,
CH2tBu), 38.7 (s, CCH3), 34.2 (vt, N ) 10.1 Hz, C1 of C6H11),
30.8 (s, CCH3), 30.4 (s, C3, C5 of C6H11), 27.4 (vt, N ) 5.1 Hz,
C2, C6 of C6H11), 25.7 (s, C4 of C6H11). 31P{1H} NMR (81.0
MHz, CDCl3): δ 52.9 (s).
Exp er im en ta l Section
Gen er a l Con sid er a tion s. All experiments were carried out
under an atmosphere of argon using Schlenk techniques. The
starting materials 1a -d 7 and [H(OEt2)2]BArf25 were prepared
as previously described. CH2FCO2Na was a product from
Aldrich. CHF2CO2Tl and CF3CO2Tl were obtained upon treat-
ment of CHF2CO2H (ABCR) and CF3CO2H (Riedel-deHae¨n)
with Tl2CO3 in THF. The sodium benzoates 2-NO2C6H4CO2-
Na, 4-NO2C6H4CO2Na, 2,4-(NO2)2C6H3CO2Na, and C6F5CO2-
Na were prepared from the corresponding benzoic acids
(Aldrich) and Na2CO3 in THF. Technical grade solvents were
dried by standard procedures and distilled under argon before
use. CDCl3 was dried over Al2O3 (basic, activity grade I), and
C6D6 as well as CD2Cl2 over 4 Å molecular sieves. NMR spectra
were recorded on Bruker AC 200 or AMX 400 instruments
usually at 293 K, unless otherwise indicated. Chemical shifts
are referred to TMS (1H and 13C{H}), 85% H3PO4 (31P{1H}),
P r ep a r a tion of [Ru Cl2(tCCH2tBu )(P iP r 3)2]BAr f (2d ).
To a solid mixture of 1d (101 mg, 0.18 mmol) and [H(OEt2)2]-
BArf (173 mg, 0.17 mmol) was added CH2Cl2 (2.5 mL) at -78
°C. After the suspension was stirred and allowed to warm to
-20 °C, a brown solution was obtained. Addition of pentane
(15 mL) led to the precipitation of a beige solid, which was
separated from the mother liquor, washed with pentane (3 ×
10 mL), and dried in vacuo: yield 224 mg (89%); mp 102 °C
dec. Anal. Calcd for C56H65BCl2F24P2Ru: C, 46.75; H, 4.55.
1
Found: C, 46.68; H, 4.25. H NMR (200 MHz, CDCl3): δ 7.73
(br m, 8H, ortho-H of Arf), 7.55 (br m, 4H, para-H of Arf), 3.31
3
(t, J PH ) 3.5 Hz, 2H, CH2tBu), 3.11 (m, 6H, PCHCH3), 1.41
3
(dvt, N ) 15.3, J HH ) 7.3 Hz, 36H, PCHCH3), 1.19 (s, 9H,
CCH3). 13C{1H} NMR (50.3 MHz, CDCl3, 278 K): δ 317.7 (t,
2J PC ) 3.8 Hz, RutC), 72.2 (s, CH2tBu), 38.8 (s, CCH3), 30.9
(s, CCH3), 24.9 (vt, N ) 10.8 Hz, PCHCH3), 19.9 (s, PCHCH3).
31P{1H} NMR (81.0 MHz, CDCl3): δ 58.9 (s).
or CFCl3 (19F{1H}). Abbreviations: app ) apparent, vt )
3
virtual triplet, dvt ) doublet of virtual triplets, N ) J PH
+
P r ep a r a t ion of [R u Cl(K2-O2CH )(dCdCH P h )(P iP r 3)2]
(3a ). A solution of 1b (693 mg, 1.16 mmol) in THF (25 mL)
was treated with HCO2Na (780 mg, 11.47 mmol), and the
resulting suspension was stirred for 22 h at room temperature.
The solvent was removed, and the residue was extracted with
diethyl ether (2 × 20 mL). The combined extracts were
evaporated in vacuo to give an orange solid, which was washed
with pentane (2 × 5 mL) at -78 °C and dried: yield 543 mg
(77%); mp 77 °C dec. Anal. Calcd for C27H49ClO2P2Ru: C,
53.68; H, 8.18. Found: C, 53.49; H, 8.18. IR (Nujol): ν(CdC)
5J P′H for 1H NMR and N ) 1J PC + 3J P′C for 13C{H} NMR data.
The 13C{H} NMR resonances of the BArf- anion are not given.
The 1H and 19F NMR data for the equilibria between com-
pounds 5 and 6 include fractional integrated values for some
of the signals, which are referred to the integrated values of
-
the signals arising from the BArf anion. IR spectra were
recorded on a Bruker IFS 25 spectrophotometer. Melting
points were determined by DTA.
P r ep a r a tion of [Ru Cl2(tCCH2P h )(P Cy3)2]BAr f (2a ). To
a solid mixture of 1a (254 mg, 0.30 mmol) and [H(OEt2)2]BArf
(308 mg, 0.30 mmol) was added CH2Cl2 (8 mL). After the
suspension was stirred for 5 min, an orange-yellow solution
was obtained. The solution was concentrated to ca. 4 mL in
vacuo, and upon addition of pentane (20 mL) a pale yellow
solid precipitated. The mother liquor was decanted, and the
remaining solid was washed with pentane (5 mL) and dried:
1
1615, νas(OCO) 1570 cm-1. H NMR (200 MHz, C6D6): δ 7.56
(t, 4J PH ) 1.8 Hz, 1H, HCO2), 7.15 (m, 4H, C6H5), 6.89 (m, 1H,
4
C6H5), 4.92 (t, J PH ) 3.3 Hz, 1H, dCHPh), 2.67 (m, 6H,
3
PCHCH3), 1.27, 1.22 (both dvt, N ) 13.2, J HH ) 6.9 Hz, 18H,
2
PCHCH3). 13C{1H} NMR (50.3 MHz, C6D6): δ 351.0 (t, J PC
)
14.6 Hz, RudC), 174.1 (s, HCO2), 133.6 (t, 4J PC ) 2.5 Hz, ipso-C
of C6H5), 128.6, 125.4, 124.3 (all s, C6H5), 110.5 (t, J PC ) 3.8
3
yield 519 mg (99%); mp 141 °C dec. Anal. Calcd for C76H85
-
1
Hz, )CHPh), 22.9 (vt, N ) 9.5 Hz, PCHCH3), 19.8, 19.6 (both
s, PCHCH3). 31P{1H} NMR (81.0 MHz, C6D6): δ 25.3 (s).
P r ep a r a tion of [Ru Cl(K2-O2CCH3)(dCdCHP h )(P iP r 3)2]
(3b). This complex was prepared as described for 3a , starting
from 1b (819 mg, 1.38 mmol) and CH3CO2Na‚3H2O (400 mg,
2.94 mmol). Orange microcrystalline solid: yield 789 mg (82%);
mp 128 °C dec. Anal. Calcd for C28H51ClO2P2Ru: C, 54.40; H,
8.32. Found: C, 54.49; H, 8.03. IR (Nujol): ν(CdC) 1610, νas-
BCl2F24P2Ru: C, 53.72; H, 5.04. Found: C, 53.48; H, 4.83. H
NMR (400 MHz, CDCl3): δ 7.72 (br m, 8H, ortho-H of Arf),
7.53 (br m, 4H, para-H of Arf), 7.40 (m, 3H, C6H5), 7.09 (m,
4
2H, C6H5), 4.51 (t, J PH ) 2.9 Hz, 2H, CH2Ph), 2.85 (m, 6H,
CH of C6H11), 1.93-1.10 (br m, 60H, CH2 of C6H11). 13C{1H}
2
NMR (100.6 MHz, CDCl3): δ 309.7 (t, J PC ) 4.4 Hz, RutC),
130.2, 130.1, 128.7, 126.4 (all s, C6H5), 62.3 (s, CH2Ph), 33.8
(vt, N ) 10.2 Hz, C1 of C6H11), 30.3 (s, C3, C5 of C6H11), 27.5

Carbene and Carbyne Ruthenium Complexes
Organometallics, Vol. 20, No. 17, 2001 3681
1
(OCO) 1553 cm-1. H NMR (200 MHz, C6D6): δ 7.17 (m, 4H,
3J PC ) 3.8 Hz, )CHPh), 22.9 (vt, N ) 9.5 Hz, PCHCH3), 19.6,
19.5 (both s, PCHCH3), signal of CF3CO2 not observed. 31P-
{1H} NMR (81.0 MHz, C6D6): δ 25.8 (s). 19F NMR (188.3 MHz,
C6D6): δ -74.91 (s).
C6H5), 6.88 (m, 1H, C6H5), 4.93 (t, 4J PH ) 3.5 Hz, 1H, dCHPh),
2.67 (m, 6H, PCHCH3), 1.72 (s, 3H, CH3CO2), 1.27 (m, 36H,
PCHCH3). 13C{1H} NMR (50.3 MHz, C6D6): δ 350.8 (t, J PC
)
2
4
P r ep a r a tion of [Ru Cl(K2-O2CP h )(dCdCHP h )(P iP r 3)2]
(3f). A solution of 1b (345 mg, 0.58 mmol) in THF (5 mL) was
treated with PhCO2H (73 mg, 0.60 mmol) and Et3N (100 µL,
0.72 mmol). After the resulting solution was stirred for 5 h at
room temperature, the solvent was removed in vacuo and the
remaining residue was extracted with pentane (30 mL). Partial
evaporation of the solvent from the extract to ca. 8 mL led to
the precipitation of an orange solid, which was washed with
cold pentane (2 × 5 mL) and dried: yield 304 mg (77%); mp
138 °C dec. Anal. Calcd for C33H53ClO2P2Ru: C, 58.27; H, 7.85.
Found: C, 58.39; H, 7.75. IR (Nujol): ν(CdC) 1608, νas(OCO)
14.6 Hz, RudC), 183.1 (s, CH3CO2), 134.0 (t, J PC ) 2.5 Hz,
ipso-C of C6H5), 128.6, 125.4, 124.1 (all s, C6H5), 111.3 (t, J PC
) 3.8 Hz, dCHPh), 24.0 (s, CH3CO2), 22.9 (vt, N ) 9.5 Hz,
PCHCH3), 19.8, 19.7 (both s, PCHCH3). 31P{1H} NMR (81.0
MHz, C6D6): δ 25.6 (s).
3
P r ep a r a tion of [Ru Cl(K2-O2CH2F )(dCdCHP h )(P iP r 3)2]
(3c). A solution of 1b (453 mg, 0.76 mmol) in THF (20 mL)
was treated with both CH2FCO2Na (80 mg, 0.80 mmol) and
CF3SO3Tl (284 mg, 0.80 mmol) and then stirred for 5 days at
room temperature. The solvent was removed, and the residue
was extracted with pentane (2 × 5 mL). The combined extracts
were evaporated in vacuo to give a beige solid, which was
washed with methanol (3 × 5 mL) at -60 °C and purified by
recrystallization from pentane at -78 °C: yield 304 mg (63%);
mp 121 °C dec. Anal. Calcd for C28H50ClFO2P2Ru: C, 52.86;
H, 7.92. Found: C, 53.12; H, 7.81. IR (Nujol): ν(CdC) 1614,
1
1524 cm-1. H NMR (400 MHz, C6D6): δ 8.21, 7.31, 7.23 (all
m, 2H each, C6H5), 7.10 (m, 3H, C6H5), 6.91 (m, 1H, C6H5),
4
4.99 (t, J PH ) 3.5 Hz, 1H, dCHPh), 2.68 (m, 6H, PCHCH3),
1.25 (m, 36H, PCHCH3). 13C{1H} NMR (100.6 MHz, C6D6): δ
2
351.0 (t, J PC ) 15.3 Hz, RudC), 177.5 (s, PhCO2), 134.0 (t,
4J PC ) 2.5 Hz, ipso-C, C6H5 of vinylidene), 133.0, 132.2, 128.8,
νas(OCO) 1578 cm-1
.
1H NMR (400 MHz, C6D6): δ 7.17 (m,
3
4
128.6, 125.4, 124.2 (all s, C6H5), 111.1 (t, J PC ) 3.8 Hz, d
4H, C6H5), 6.87 (m, 1H, C6H5), 4.91 (t, J PH ) 3.5 Hz, 1H,
2
CHPh), 22.9 (vt, N ) 9.5 Hz, PCHCH3), 19.8, 19.7 (both s,
PCHCH3). 31P{1H} NMR (162.0 MHz, C6D6): δ 25.3 (s).
P r ep a r a tion of [Ru Cl(K2-O2CC6H4NO2-4)(dCdCHP h )-
(P iP r 3)2] (3g). A solution of 1b (367 mg, 0.62 mmol) in THF
(20 mL) was treated with 4-NO2C6H4CO2Na (212 mg, 1.12
mmol) and stirred for 16 h at room temperature. A red
suspension was obtained, from which the solvent was removed
in vacuo. The residue was extracted with dichloromethane (10
mL), and the extract was evaporated in vacuo. After the
remaining residue was treated with methanol (8 mL), a yellow-
orange solid precipitated, which was filtered, washed with
methanol (3 × 5 mL), and recrystallized from dichloromethane/
pentane: yield 358 mg (80%); mp 159 °C. Anal. Calcd for
dCHPh), 4.38 (d, J FH ) 47.5 Hz, 2H, CH2F), 2.62 (m, 6H,
PCHCH3), 1.23 (m, 36H, PCHCH3). 13C{1H} NMR (100.6 MHz,
C6D6): δ 352.0 (t, 2J PC ) 15.2 Hz, RudC), 178.1 (d, 2J FC ) 20.3
4
Hz, CH2FCO2), 133.4 (t, J PC ) 2.5 Hz, ipso-C of C6H5), 128.7,
3
125.5, 124.5, 124.4 (all s, C6H5), 111.1 (t, J PC ) 3.8 Hz,
1
dCHPh), 79.1 (d, J FC ) 183.1 Hz, CH2F), 23.0 (vt, N ) 8.9
Hz, PCHCH3), 19.7, 19.6 (both s, PCHCH3). 31P{1H} NMR
(162.0 MHz, C6D6): δ 25.1 (s). 19F{1H} NMR (376.4 MHz,
C6D6): δ -227.1 (s).
P r ep a r a tion of [Ru Cl(K2-O2CHF 2)(dCdCHP h )(P iP r 3)2]
(3d ). A solution of CHF2CO2Tl (308 mg, 1.03 mmol) in THF
(50 mL) was added dropwise to a stirred solution of 1b in THF
(10 mL) over a period of 1 h. After the resulting suspension
was stirred for 3.5 h at room temperature, the solvent was
removed and the residue was extracted with pentane (25 + 5
mL). Partial evaporation of the solvent from the combined
extracts to ca. 8 mL led to the precipitation of an orange solid,
which was washed with pentane (2 × 5 mL) at -78 °C and
C
33H52ClNO4P2Ru: C, 54.65; H, 7.23; N, 1.93. Found: C, 54.37;
H, 6.97; N, 1.90. IR (Nujol): ν(CdC) 1615, νas(NO2) 1548,
1
νas(OCO) 1522 cm-1. H NMR (400 MHz, C6D6): δ 7.89, 7.69
(AB system, 3J HH ) 8.8 Hz, 4H, C6H4), 7.26 (m, 4H, C6H5), 6.94
4
(m, 1H, C6H5), 4.99 (t, J PH ) 3.5 Hz, 1H, dCHPh), 2.65 (m,
6H, PCHCH3), 1.23 (m, 36H, PCHCH3). 13C{1H} NMR (100.6
dried: yield 472 mg (71%); mp 110 °C. Anal. Calcd for C28H49
-
2
MHz, C6D6): δ 352.0 (t, J PC ) 15.3 Hz, RudC), 175.1 (s,
ClF2O2P2Ru: C, 51.41; H, 7.55. Found: C, 51.17; H, 7.68. IR
C6H4CO2), 150.1 (s, C4 of C6H4), 133.5 (t, 4J PC ) 2.5 Hz, ipso-C
of C6H5), 129.3, 128.7, 125.5, 124.5, 123.8 (all s, C6H5 and
C6H4), 111.1 (t, 3J PC ) 3.8 Hz, dCHPh), 22.9 (vt, N ) 10.2 Hz,
PCHCH3), 19.7, 19.6 (both s, PCHCH3). 31P{1H} NMR (162.0
MHz, C6D6): δ 25.2 (s).
(Nujol): ν(CdC) 1602, νas(OCO) 1571 cm-1. 1H NMR (400 MHz,
2
C6D6): δ 7.15 (m, 4H, C6H5), 6.88 (m, 1H, C6H5), 5.32 (t, J FH
4
) 53.7 Hz, 1H, CHF2), 4.91 (t, J PH ) 3.5 Hz, 1H, dCHPh),
2.61 (m, 6H, PCHCH3), 1.22 (m, 36H, PCHCH3). 13C{1H} NMR
2
(100.6 MHz, C6D6): δ 352.8 (t, J PC ) 15.2 Hz, RudC), 171.6
2
4
P r ep a r a tion of [Ru Cl(K2-O2CC6H4NO2-2)(dCdCHP h )-
(P iP r 3)2] (3h ). This complex was prepared as described for
3g, starting from 1b (304 mg, 0.51 mmol) and 2-NO2C6H4CO2-
Na (145 mg, 0.77 mmol). Yellow-orange solid: yield 181 mg
(49%); mp 162 °C dec. Anal. Calcd for C33H52ClNO4P2Ru: C,
54.65; H, 7.23; N, 1.93. Found: C, 54.17; H, 6.88; N, 1.91. IR
(Nujol): ν(CdC) 1615, νas(NO2) 1539 cm-1. 1H NMR (400 MHz,
(t, J FC ) 27.9 Hz, CHF2CO2), 132.9 (t, J PC ) 2.5 Hz, ipso-C
3
of C6H5), 128.7, 125.5, 124.6 (all s, C6H5), 111.1 (t, J PC ) 3.8
1
Hz, )CHPh), 106.8 (t, J FC ) 249.2 Hz, CHF2), 22.9 (vt, N )
8.9 Hz, PCHCH3), 19.7, 19.6 (both s, PCHCH3). 31P{1H} NMR
(162.0 MHz, C6D6): δ 24.9 (s). 19F{1H} NMR (376.4 MHz,
C6D6): δ -125.1 (s).
P r ep a r a tion of [Ru Cl(K2-O2CCF 3)(dCdCHP h )(P iP r 3)2]
(3e). A solution of CF3CO2Tl (432 mg, 1.36 mmol) in THF (30
mL) was added dropwise to a stirred solution of 1b (809 mg,
1.36 mmol) in THF (10 mL) over a period of 30 min. After the
resulting suspension was stirred for 30 min, the solvent was
removed in vacuo and the residue was extracted with pentane
(2 × 15 mL). Evaporation of the solvent from the combined
extracts led to the formation of an oil, which, after drying in
vacuo for 4 h, gave a dark brown solid: yield 866 mg. The solid
contained approximately 84% of 3e, 8% of 1b, and 8% of 4b.
Complex 3e could not be purified by either recrystallization
or chromatography. Spectroscopic data for 3e: IR (Nujol):
C6D6): δ 8.15 (m, 1H, C6H4), 7.30 (m, 4H, C6H5), 6.95 (m, 1H,
4
C6H5), 6.77 (m, 1H, C6H4), 6.60 (m, 2H, C6H4), 5.01 (t, J PH
)
3.5 Hz, 1H, dCHPh), 2.66 (m, 6H, PCHCH3), 1.28, 1.22 (both
dvt, N ) 13.2, J HH ) 7.0 Hz, 18H each, PCHCH3). 13C{1H}
3
2
NMR (100.6 MHz, C6D6): δ 352.6 (t, J PC ) 15.2 Hz, RudC),
4
172.2 (s, C6H4CO2), 151.3 (s, C2,6 of C6H4), 133.4 (t, J PC
)
2.5 Hz, ipso-C of C6H5), 132.9, 131.1, 129.8, 128.8, 125.7, 124.4,
122.5, 122.4 (all s, C6H5 and C6H4), 111.0 (t, J PC ) 3.8 Hz,
3
dCHPh), 22.9 (vt, N ) 8.9 Hz, PCHCH3), 19.8, 19.7 (both s,
PCHCH3). 31P{1H} NMR (162.0 MHz, C6D6): δ 25.2 (s).
P r ep a r a tion of [Ru Cl(K2-O2CC6F 5)(dCdCHP h )(P iP r 3)2]
(3i). A solution of 1b (313 mg, 0.53 mmol) in THF (20 mL)
was treated with C6F5CO2Na (182 mg, 0.78 mmol) and stirred
for 30 h at room temperature. A red-orange suspension was
obtained, from which the solvent was evaporated in vacuo. The
residue was extracted with pentane (15 mL), and the extract
was brought to dryness in vacuo. After the residue was treated
ν(CdC) 1615 cm-1
.
1H NMR (200 MHz, C6D6): δ 7.17 (m,
4
4H, C6H5), 6.87 (m, 1H, C6H5), 4.93 (t, J PH ) 3.3 Hz, 1H, d
CHPh), 2.57 (m, 6H, PCHCH3), 1.20 (m, 36H, PCHCH3).
13C{1H} NMR (50.3 MHz, C6D6): δ 353.7 (t, J PC ) 15.3 Hz,
2
RudC), 164.8 (q, 2J FC ) 39.4 Hz, CF3CO2), 132.5 (t, 4J PC ) 2.5
Hz, ipso-C of C6H5), 128.8, 125.6, 124.8 (all s, C6H5), 111.1 (t,

3682 Organometallics, Vol. 20, No. 17, 2001
Gonza´lez-Herrero et al.
3
with methanol (8 mL), a red-orange solid precipitated, which
was washed with cold methanol (2 × 5 mL) and recrystallized
from pentane at -78 °C: yield 360 mg (89%); mp 132 °C. Anal.
Calcd for C33H48ClF5O2P2Ru: C, 51.46; H, 6.28. Found: C,
6H, PCHCH3), 1.12 (dvt, N ) 13.2, J HH ) 6.9 Hz, 36H,
PCHCH3). 13C{1H} NMR (50.3 MHz, C6D6): δ 362.1 (t, J PC
)
2
2
15.3 Hz, RudC), 163.5 (q, J CF ) 38.1 Hz, CF3CO2), 132.2 (t,
4J PC ) 2.5 Hz, ipso-C of C6H5), 128.9, 125.8, 125.2 (all s, C6H5),
1
1
3
51.57; H, 5.96. IR (Nujol): ν(CdC) 1610 cm-1. H NMR (400
114.3 (q, J CF ) 288.5 Hz, CF3CO2), 113.0 (t, J PC ) 3.8 Hz,
dCHPh), 23.3 (vt, N ) 8.9 Hz, PCHCH3), 19.3 (s, PCHCH3).
31P{1H} NMR (81.0 MHz, C6D6): δ 27.8 (s). 19F NMR (188.3
MHz, C6D6): δ -74.2 (s).
MHz, C6D6): δ 7.21 (m, 4H, C6H5), 6.89 (m, 1H, C6H5), 4.99 (t,
4J PH ) 3.5 Hz, 1H, dCHPh), 2.73 (m, 6H, PCHCH3), 1.27 (m,
36H, PCHCH3). 13C{1H} NMR (100.6 MHz, C6D6): δ 352.4 (t,
4
2J PC ) 15.2 Hz, RudC), 168.3 (br m, C6F5CO2), 133.1 (t, J PC
P r ep a r a tion of [Ru (K1-O2CCF 3)(K2-O2CH)(dCdCHP h )-
(P iP r 3)2] (4c). A solution of 4b (323 mg, 0.43 mmol) in THF
(15 mL) was treated with HCO2Na (186 mg, 2.74 mmol) and
stirred for 5.5 h at room temperature. The reaction mixture
was then worked up as described for 4b. Orange crystals
(containing 1/3 molecule of pentane per formula unit) were
obtained after recrystallization from pentane at -78 °C: yield
213 mg (72%); mp 58 °C dec, Anal. Calcd for C30.67H53F3O4P2-
Ru: C, 52.19; H, 7.57. Found: C, 52.25; H, 7.54. IR (Nujol):
νas(OCO) of κ1-O2CCF3 1701, ν(CdC) 1617, νas(OCO) of
κ2-O2CH 1550 cm-1. 1H NMR (200 MHz, C6D6): δ 7.41 (t, 4J PH
) 1.8 Hz, 1H, HCO2), 7.19 (m, 4H, C6H5), 6.87 (m, 1H, C6H5),
) 2.5 Hz, ipso-C of C6H5), 128.2, 125.6, 124.6 (all s, C6H5), 111.0
3
(t, J PC ) 3.8 Hz, dCHPh), 22.9 (vt, N ) 10.2 Hz, PCHCH3),
19.7, 19.6 (both s, PCHCH3). 31P{1H} NMR (162.0 MHz,
C6D6): δ 25.3 (s). 19F{1H} NMR (376.4 MHz, C6D6): δ -139.0
(m, 2F, C6F5), -148.5 (m, 1F, C6F5), -160.9 (m, 2F, C6F5).
P r ep a r a tion of [Ru Cl{K2-O2CC6H3(NO2)2-2,4}(dCd
CHP h )(P iP r 3)2] (3j). This compound was prepared as de-
scribed for 3g, starting from 1b (311 mg, 0.52 mmol) and 2,4-
(NO2)2C6H4CO2Na (142 mg, 0.63 mmol). Orange microcrystalline
solid: yield 275 mg (68%); mp 146 °C dec. Anal. Calcd for
C
33H51ClN2O6P2Ru: C, 51.46; H, 6.67; N, 3.64. Found: C,
3
5.98 (t, J PH ) 3.3 Hz, 1H, dCHPh), 2.26 (m, 6H, PCHCH3),
50.55; H, 6.14; N, 3.45. IR (Nujol): ν(CdC) 1611, νas(OCO)
3
1
1569, νas(NO2) 1550, 1539 cm-1. H NMR (400 MHz, C6D6): δ
1.16 (dvt, N ) 13.2, J HH ) 6.9 Hz, 18H, PCHCH3), 1.15 (dvt,
N ) 12.9, J HH ) 7.1 Hz, 18H, PCHCH3). 13C{1H} NMR (50.3
3
7.85 (d, J HH ) 8.5 Hz, 1H, H6 of C6H4), 7.34 (m, 4H, H3,5 of
C6H5 and H3,5 of C6H4), 7.23 (m, 2H, H2,6 of C6H5), 6.97 (m,
1H, H4 of C6H5), 5.01 (t, 4J PH ) 3.5 Hz, 1H, dCHPh), 2.63 (m,
2
MHz, C6D6): δ 359.0 (t, J PC ) 15.3 Hz, RudC), 174.5 (s,
2
4
HCO2), 161.4 (q, J FC ) 36.9 Hz, CF3CO2), 133.3 (t, J PC ) 2.5
Hz, ipso-C of C6H5), 128.7, 125.6, 124.6 (all s, C6H5), 112.4 (t,
3J PC ) 4.4 Hz, dCHPh), 23.2 (vt, N ) 8.9 Hz, PCHCH3), 19.5
(s, PCHCH3), 19.4 (s, PCHCH3), signal of CF3CO2 not observed.
31P{1H} NMR (81.0 MHz, C6D6): δ 27.5 (s). 19F NMR (188.3
MHz, C6D6): δ -73.74 (s).
3
6H, PCHCH3), 1.26, 1.21 (both dvt, N ) 13.2, J HH ) 7.0 Hz,
18H each, PCHCH3). 13C{1H} NMR (100.6 MHz, C6D6): δ 353.4
2
(t, J PC ) 15.3 Hz, RudC), 170.0 (s, C6H4CO2), 150.2, 149.3
(both s, C2,4 of C6H4), 132.9 (br m, ipso-C of C6H5), 132.1, 128.8,
125.9, 125.7, 124.7, 124.5, 118.2 (all s, C6H5 and C6H4), 111.0
3
(t, J PC ) 3.8 Hz, dCHPh), 22.9 (vt, N ) 10.2 Hz, PCHCH3),
P r ep a r a tion of [Ru Cl{dC(CH2P h )OC(O)H}(P iP r 3)2]-
BAr f (6a ). A solid mixture of 3a (157 mg, 0.26 mmol) and
[H(OEt2)2]BArf (260 mg, 0.26 mmol) was treated with dichlo-
romethane (3 mL), and the resulting dark red solution was
stirred for 5 min at room temperature. Additon of pentane (25
mL) led to the precipitation of a red microcrystalline solid,
which was separated from the mother liquor, washed with
pentane (5 mL), and dried: yield 376 mg (98%); mp 100 °C
dec. Anal. Calcd for C59H62BClF24O2P2Ru: C, 48.26; H, 4.26.
19.8, 19.6 (both s, PCHCH3). 31P{1H} NMR (162.0 MHz,
C6D6): δ 25.2 (s).
P r ep a r a t ion of [R u (K1-O2CCH F 2)(K2-O2CCH F 2)(dCd
CHP h )(P iP r 3)2] (4a ). A solution of 1b (502 mg, 0.85 mmol)
in THF (20 mL) was treated with CHF2CO2Tl (572 mg, 1.91
mmol) and stirred for 3 days at room temperature. A white
solid of TlCl precipitated, and the color of the solution changed
from violet to orange. The solvent was removed in vacuo, and
the residue was extracted with pentane (25 + 5 mL). The
combined extracts were concentrated to ca. 8 mL in vacuo, and
the solution was stored for 12 h at -78 °C. Orange crystals
precipitated, which were washed with pentane (-78 °C) and
dried: yield 462 mg (77%). Since the product slowly decom-
poses in solution, forming an unidentified insoluble yellow
solid, it could not be purified by recrystallization. Therefore,
no satisfactory elemental analyses were obtained. Data for
1
Found: C, 48.02; H, 4.23. H NMR (200 MHz, CDCl3): δ 8.24
(s, 1H, HCO2), 7.72 (br m, 8H, ortho-H of Arf), 7.54 (br m, 4H,
para-H of Arf), 7.39 (m, 5H, C6H5), 5.00 (s, 2H, CH2Ph), 2.93
3
(m, 6H, PCHCH3), 1.25, 1.16 (both dvt, N ) 14.6, J HH ) 7.3
Hz, 18H each, PCHCH3). 13C{1H} NMR (50.3 MHz, CDCl3): δ
2
286.9 (t, J PC ) 5.1 Hz, RudC), 170.0 (s, HCO2), 130.8, 129.9,
128.8, 128.5 (all s, C6H5), 60.5 (s, CH2Ph), 23.2 (vt, N ) 10.2
Hz, PCHCH3), 19.0, 18.6 (both s, PCHCH3). 31P{1H} NMR (81.0
MHz, CDCl3): δ 48.0 (s).
4a : IR (Nujol): ν(CdC) 1622, νas(OCO) 1691, 1675 cm-1 1H
.
NMR (400 MHz, C6D6): δ 7.20 (m, 4H, C6H5), 6.89 (m, 1H,
C6H5), 6.07 (t, 4J PH ) 3.5 Hz, 1H, dCHPh), 5.52 (t, 2J FH ) 54.6
Hz, 2H, CHF2), 2.27 (m, 6H, PCHCH3), 1.17 (dvt, N ) 13.2,
3J HH ) 7.0 Hz, 36H, PCHCH3). 13C{1H} NMR (100.6 MHz,
C6D6): δ 359.3 (t, 2J PC ) 15.3 Hz, RudC), 169.6 (t, 2J FC ) 26.7
P r ep a r a tion of [Ru Cl{dC(CH2P h )OC(O)CH3}(P iP r 3)2]-
BAr f (6b). This complex was prepared as described for 6a ,
starting from 3b (172 mg, 0.28 mmol) and [H(OEt2)2]BArf (282
mg, 0.28 mmol). Red microcrystalline solid: yield 389 mg
(92%); mp 101 °C dec. Anal. Calcd for C60H64BClF24O2P2Ru:
C, 48.61; H, 4.35. Found: C, 48.50; H, 4.38. IR (Nujol):
4
Hz, CHF2CO2), 133.1 (t, J PC ) 2.5 Hz, ipso-C of C6H5), 128.3,
3
1
ν(CdO) 1633 cm-1. H NMR (200 MHz, CDCl3): δ 7.73 (br m,
125.6, 124.7 (all s, C6H5), 113.0 (t, J PC ) 4.4 Hz, dCHPh),
1
107.3 (t, J FC ) 250.5 Hz, CHF2), 23.3 (vt, N ) 8.9 Hz,
8H, ortho-H of BArf), 7.56 (br m 4H, para-H of BArf), 7.38 (m,
PCHCH3), 19.5 (s, PCHCH3). 31P{1H} NMR (162.0 MHz,
C6D6): δ 27.1 (s). 19F{1H} NMR (376.4 MHz, C6D6): δ -123.5
(s).
5H, C6H5), 4.96 (s, 2H, CH2Ph), 2.68 (s, 3H, CH3CO2), 2.33 (br
3
m, 6H, PCHCH3), 1.22 (dvt, N ) 14.6, J HH ) 7.3 Hz, 18H,
PCHCH3), 1.14 (dvt, N ) 14.2, 3J HH ) 6.9 Hz, 18H, PCHCH3).
2
13C{1H} NMR (50.3 MHz, CDCl3, 253 K): δ 287.0 (t, J PC
)
P r epar ation of [Ru (K1-O2CCF3)(K2-O2CCF3)(dCdCHP h )-
(P iP r 3)2] (4b). A solution of 1b (595 mg, 1.00 mmol) in acetone
(25 mL) was treated with CF3CO2Tl (790 mg, 2.49 mmol) and
stirred for 20 h at room temperature. The solvent was removed
in vacuo, the residue was extracted with pentane (25 mL), and
the extract was concentrated in vacuo to ca. 3 mL. An orange
solid precipitated, which was washed with pentane (2 × 5 mL)
at -78 °C and dried: yield 647 mg (86%); mp 105 °C dec. Anal.
Calcd for C30H48F6O4P2Ru: C, 48.06; H, 6.45. Found: C, 47.75;
H, 6.12. IR (Nujol): νas(OCO) of κ1-O2CCF3 1701, ν(CdC) 1614
5.1 Hz, RudC), 182.6 (s, CH3CO2), 131.3, 129.8, 128.7, 128.3
(all s, C6H5), 60.3 (s, CH2Ph), 23.3 (vt, N ) 10.7 Hz, PCHCH3),
19.0, 18.6 (both s, PCHCH3), 18.0 (s, CH3CO2). 31P{1H} NMR
(81.0 MHz, CDCl3): δ 47.1 (s).
P r ep a r a t ion of [R u Cl{dC(CH2P h )OC(O)CH2F }(P i-
P r 3)2]BAr f (6c). A solid mixture of 3c (121 mg, 0.19 mmol)
and [H(OEt2)2]BArf (184 mg, 0.18 mmol) was treated with
dichloromethane (3 mL) at -78 °C. The resulting suspension
was stirred for 10 min and then allowed to warm to room
temperature. Addition of pentane (20 mL) led to the precipita-
tion of an orange solid, which was separated from the mother
cm-1
.
1H NMR (200 MHz, C6D6): δ 7.15 (m, 4H, C6H5), 6.87
4
(m, 1H, C6H5), 6.05 (t, J PH ) 3.3 Hz, 1H, dCHPh), 2.22 (m,

Carbene and Carbyne Ruthenium Complexes
Organometallics, Vol. 20, No. 17, 2001 3683
liquor and washed with small quantities of pentane (0 °C). It
was recrystallized from dichloromethane/pentane and dried:
yield 242 mg (89%); mp 95 °C dec. The NMR data indicated
that in solution (CD2Cl2) both isomers 6c and 5c (molar ratio
9:1) are present. Anal. Calcd for C60H63BClF25O2P2Ru: C,
48.03; H, 4.23. Found: C, 47.90; H, 4.04. IR (Nujol): ν(CdO)
1632 cm-1; 1H NMR (400 MHz, CD2Cl2, 233 K): δ 7.72 (br m,
8H, ortho-H, BArf), 7.55 (br m, 4H, para-H, BArf), 7.37 (m,
(s, 24F, CF3 of Arf), -72.9 (s, 1.1F, CF3CO2 of 6e), -75.1 (s,
2.9F, CF3CO2 of 5e).
P r ep a r a tion of [Ru Cl{dC(CH2P h )OC(O)P h }(P iP r 3)2]-
BAr f (6f). This complex was prepared as described for 6c,
starting from 3f (162 mg, 0.24 mmol) and [H(OEt2)2]BArf (238
mg, 0.24 mmol). Purple microcrystalline solid: yield: 345 mg
(95%); mp 111 °C dec. Anal. Calcd for C65H66BClF24O2P2Ru:
C, 50.55; H, 4.31. Found: C, 50.53; H, 4.43. 1H NMR (400 MHz,
CDCl3): δ 8.03 (m, 2H, C6H5), 7.70 (m, 9H, ortho-H of Arf,
C6H5), 7.53 (m, 8H, para-H of Arf, C6H5), 7.39 (m, 3H, C6H5),
5.10 (s, 2H, CH2Ph), 2.42 (m, 6H, PCHCH3), 1.28, 1.19 (both
2
5H, C6H5), 5.62 (d, J FH ) 45.2 Hz, 1.8H, CH2F of 6c), 4.97 (s,
2
1.8H, CH2Ph of 6c), 4.81 (d, J FH ) 46.4 Hz, 0.2H, CH2F of
5c), 4.53 (s, 0.2H, CH2Ph of 5c), 2.54 (m, 0.6H, PCHCH3 of
5c), 2.35 (m, 5.4H, PCHCH3 of 6c), 1.24, 1.13 (both dvt, N )
3
dvt, N ) 14.4, J HH ) 7.3 Hz, 18H each, PCHCH3). 13C{1H}
2
3
14.4, J HH ) 7.3 Hz, 18H each, PCHCH3). 13C{1H} NMR of 6c
NMR (100.6 MHz, CDCl3): δ 287.4 (t, J PC ) 5.1 Hz, RudC),
2
177.4 (s, PhCO2), 138.1, 131.7, 130.6, 130.4, 130.0, 128.9, 128.6,
121.6 (all s, C6H5), 60.5 (s, CH2Ph), 23.8 (vt, N ) 10.8 Hz,
PCHCH3), 19.3, 18.9 (both s, PCHCH3). 31P{1H} NMR (162
MHz, CDCl3): δ 47.1 (s).
(50.3 MHz, CD2Cl2, 243 K): δ 285.4 (t, J PC ) 5.1 Hz, RudC),
178.6 (d, 2J CF ) 22.9 Hz, CH2FCO2), 131.0, 129.9, 128.7 (all s,
1
C6H5), 76.5 (d, J FC ) 189.4 Hz, CH2FCO2), 60.5 (s, CH2Ph),
23.4 (vt, N ) 10.8 Hz, PCHCH3), 19.0, 18.5 (both s, PCHCH3).
31P{1H} NMR (162.0 MHz, CD2Cl2, 233 K): δ 49.7 (s, 5c), 47.6
(s, 6c). 19F{1H} NMR (376.4 MHz, CD2Cl2, 233 K): -62.5 (s,
24F, CF3 of Arf), -229.9 (s, 0.1F, CH2F of 5c), -233.1 (s, 0.9F,
CH2F of 6c).
P r ep a r a tion of [Ru Cl{dC(CH2P h )OC(O)C6H4NO2-4}-
(P iP r 3)2]BAr f (6g). This complex was prepared as described
for 6c, starting from 3g (94 mg, 0.13 mmol) and [H(OEt2)2]-
BArf (124 mg, 0.12 mmol). Dark green microcrystalline solid:
yield 182 mg (93%); mp 106 °C dec. Anal. Calcd for C65H65
-
P r ep a r a tion of [Ru Cl(K2-O2CCHF2)(tCCH2P h )(P iP r 3)2]-
BAr f (5d ). Following the procedure described for the prepara-
tion of 6c, treatment of 3d (193 mg, 0.29 mmol) and [H(OEt2)2]-
BArf (293 mg, 0.29 mmol) with dichloromethane (3 mL) at -78
°C finally led to an orange-red microcrystalline solid, which
consisted of a mixture of 5d and 6d . If a solution of this solid
in dichloromethane (3 mL) was stored at -78 °C for 6 days,
yellow crystals of 5d were obtained: yield 421 mg (96%); mp
82 °C dec. The NMR data indicated that in solution (CD2Cl2)
both isomers 5d and 6d (molar ratio ca. 8:1) are present. Anal.
Calcd for C60H62BClF26O2P2Ru: C, 47.46; H, 4.12. Found: C,
47.20, 4.32. IR for 5d (Nujol): νas(OCO) 1584 cm-1, for the
mixture 5d /6d an additional ν(CdO) band at 1643 cm-1 is
BClF24NO4P2Ru: C, 49.12; H, 4.12; N, 0.88. Found: C, 48.90;
H, 4.02; N, 0.92. IR (Nujol): νas(NO2) 1537 cm-1. 1H NMR (200
MHz, CD2Cl2, 243 K): δ 8.43, 8.26 (AB system, 3J HH ) 8.4 Hz,
4H, C6H4), 7.72 (br m, 8H, ortho-H of Arf), 7.53 (br m, 4H,
para-H of Arf), 7.43 (m, 5H, C6H5), 5.09 (s, 2H, CH2Ph), 2.33
3
(m, 6H, PCHCH3), 1.26, 1.12 (both dvt, N ) 14.6, J HH ) 7.3
Hz, 18H each, PCHCH3). 13C{1H} NMR (50.3 MHz, CD2Cl2,
2
243 K): δ 285.8 (t, J PC ) 5.1 Hz, RudC), 175.8 (s, C6H4CO2),
152.4 (s, C4 of C6H4), 132.0, 131.4, 129.9, 128.8, 128.4, 125.6,
125.3 (all s, C6H5 and C6H4), 60.3 (s, CH2Ph), 23.4 (vt, N )
10.2 Hz, PCHCH3), 19.1, 18.5 (both s, PCHCH3). 31P{1H} NMR
(81.0 MHz, CD2Cl2, 243 K): δ 48.2 (s).
P r ep a r a tion of [Ru Cl{dC(CH2P h )OC(O)C6H4NO2-2}-
(P iP r 3)2]BAr f (6h ). This complex was prepared as de-
scribed for 6c, starting from 3h (60 mg, 0.08 mmol) and
[H(OEt2)2]BArf (83 mg, 0.08 mmol). Dark violet microcrystal-
line solid: yield 113 mg (85%); mp 93 °C dec. Anal. Calcd for
1
observed. H NMR (400 MHz, CD2Cl2, 190 K): δ 7.73 (br m,
8H, ortho-H of Arf), 7.53 (s, 4H, para-H of Arf), 7.36 (m, 5H,
C6H5), 6.58 (t, 2J FH ) 51.6 Hz, 0.1H, CHF2 of 6d ), 5.84 (t, 2J FH
) 52.5 Hz, 0.9H, CHF2 of 5d ), 5.01 (s, 0.2H, CH2Ph of 6d ),
4.55 (s, 1.8H, CH2Ph of 5d ), 2.48 (br m, PCHCH3 of 5d ), 2.34
(br m, PCHCH3 of 6d ), 1.22 (br m, PCHCH3 of 5d ), 1.08 (br
m, PCHCH3 of 6d ). 13C{1H} NMR of 5d (50.3 MHz, CD2Cl2,
243 K): δ 330.0 (t, 2J PC ) 7.6 Hz, RutC), 174.7 (t, 2J CF ) 29.2
Hz, CHF2CO2), 129.9, 129.7, 128.9, 125.6 (all s, C6H5), 105.1
C
65H65BClF24NO4P2Ru: C, 49.12; H, 4.12; N, 0.88. Found: C,
48.85; H, 4.27; N, 0.92. IR (Nujol): νas(NO2) 1550 cm-1 1H
.
NMR (200 MHz, CD2Cl2, 243 K): δ 7.87 (m, 2H, C6H4), 7.73
(br m, 10H, ortho-H of Arf and C6H4), 7.55 (br m, 4H, para-H
of Arf), 7.42 (m, 5H, C6H5), 5.06 (s, 2H, CH2Ph), 2.38 (m, 6H,
1
(t, J CF ) 247.8 Hz, CHF2CO2), 64.1 (s, CH2Ph), 24.3 (vt, N )
3
PCHCH3), 1.31, 1.11 (both dvt, N ) 14.6, J HH ) 7.3 Hz, 18H
10.2 Hz, PCHCH3), 19.9, 18.3 (both s, PCHCH3). 31P{1H} NMR
(162 MHz, CD2Cl2, 193 K): δ 51.1 (s, 6d ), 49.7 (s, 5d ). 19F-
{1H} NMR (376.4 MHz, CD2Cl2, 193 K): -62.3 (s, 24F, CF3 of
Arf), -123.0 (s, 0.2F, CHF2 of 6d ), -126.7 (s, 1.8F, CHF2 of
5d ).
each, PCHCH3). 13C{1H} NMR (50.3 MHz, CD2Cl2, 243 K): δ
2
284.9 (t, J PC ) 5.1 Hz, RudC), 173.8 (s, C6H4CO2), 150.4 (s,
C2 of C6H4), 138.6, 132.7, 131.4, 130.1, 128.8, 124.6, 113.2 (all
s, C6H5 and C6H4), 60.5 (s, CH2Ph), 23.3 (vt, N ) 10.2 Hz,
PCHCH3), 19.1, 18.6 (both s, PCHCH3). 31P{1H} NMR (81.0
MHz, CD2Cl2, 243 K): δ 49.1 (s).
P r ep a r a tion of [Ru Cl(K2-O2CCF 3)(tCCH2P h )(P iP r 3)2]-
BAr f (5e). This complex was prepared following the procedure
described for 6c, starting from [H(OEt2)2]BArf (268 mg, 0.27
mmol) and the mixture containing 84% of 3e, 8% of 1b, and
8% of 4b (181 mg, 0.27 mmol of Ru). The crude product was
purified by recrystallization from dichloromethane (2 mL) at
-78 °C to give yellow crystals: yield 347 mg (99% based on
initial content of complex 3e in the starting material); mp 97
°C dec. The NMR data indicated that in solution (CD2Cl2) both
isomers 5e and 6e (molar ratio ca. 2:1) are present. Anal. Calcd
for C60H61BClF27O2P2Ru: C, 46.91; H, 4.00. Found: C, 46.58,
3.78. 1H NMR (400 MHz, CD2Cl2, 193 K): δ 7.73 (br m, 8H,
ortho-H of Arf), 7.53 (s, 4H, para-H of Arf), 7.36 (m, 5H, C6H5),
5.20 (br s, 0.7H, CH2Ph of 6e), 4.59 (br s, 1.3H, CH2Ph of 5e),
2.62 (br m, PCHCH3 of 6e), 2.48 (br m, PCHCH3 of 5e), 1.21
(m, 36H, PCHCH3). 13C{1H} NMR (100.6 MHz, CD2Cl2, 253
K): δ 130.4, 130.3, 129.7, 128.6 (all s, C6H5), 64.9 (s, CH2Ph),
24.8 (vt, N ) 10.2 Hz, PCHCH3), 19.6, 19.0 (both s, PCHCH3),
signals for RudC, CF3CO2, and CF3CO2 not exactly located.
31P{1H} NMR (162.0 MHz, CD2Cl2, 193 K): δ 61.6 (s, 5e), 50.8
(br, 6e). 19F{1H} NMR (376.4 MHz, CD2Cl2, 193 K): δ -62.7
P r ep a r a tion of [Ru Cl{dC(CH2P h )OC(O)C6F 5}(P iP r 3)2]-
BAr f (6i). This complex was prepared as described for 6c,
starting from 3i (277 mg, 0.36 mmol) and [H(OEt2)2]BArf (359
mg, 0.36 mmol). Dark violet microcrystalline solid: yield 552
mg (94%); mp 106 °C dec. The NMR data indicated that in
solution (CD2Cl2) both isomers 6i and 5i (molar ratio ca. 19:1)
are present. Anal. Calcd for C65H61BClF29O2P2Ru: C, 47.77;
H, 3.76. Found: C, 47.59; H, 3.78. 1H NMR (400 MHz,
CD2Cl2, 233 K): δ 7.72 (s, 8H, ortho-H of Arf), 7.55 (s, 4H,
para-H of Arf), 7.39 (m, 5H, C6H5), 5.09 (s, 1.9H, CH2Ph of
6i), 4.54 (br s, 0.1H, CH2Ph of 5i), 2.56 (br m, PCHCH3 of 5i),
2.35 (m, PCHCH3 of 6i), 1.28, 1.11 (both dvt, N ) 14.6, 3J HH
)
7.3 Hz, 18H each, PCHCH3). 13C{1H} NMR of 6i (100.6
MHz, CD2Cl2, 243 K): δ 286.7 (t, 2J PC ) 5.1 Hz, RudC), 170.4
(s, C6F5CO2), 131.3, 130.3, 128.8, 128.5 (all s, C6H5), 60.9 (s,
CH2Ph), 23.6 (vt, N ) 10.2 Hz, PCHCH3), 19.2, 18.7 (both s,
PCHCH3). 31P{1H} NMR (162.0 MHz, CD2Cl2, 233 K): δ 49.2
(br s, 5i), 48.4 (s, 6i). 19F NMR (376.4 MHz, CD2Cl2, 243 K,
data for 6i): δ -62.6 (s, 24F, CF3 of Arf), -131.7 (m, 2F, C6F5),
-135.6 (m, 1F, C6F5), -156.3 (m, 2F, C6F5).

3684 Organometallics, Vol. 20, No. 17, 2001
Ta ble 2. Cr ysta llogr a p h ic Da ta for 2b‚1/2CH2Cl2, 5e, a n d 6a
Gonza´lez-Herrero et al.
2b•1/2CH2Cl2
5e
6a
formula
M
C
58.50H62BCl3F24P2Ru
C60H61BClF27O2P2Ru
1536.36
C59H62BClF24O2P2Ru
1468.36
1501.25
cryst size, mm
cryst syst
space group
a, Å
0.20 × 0.15 × 0.15
0.21 × 0.19 × 0.15
0.25 × 0.20 × 0.20
triclinic
monoclinic
monoclinic
P1h (No. 2)
18.693(4)
P21/n (No. 14)
18.882(3)
P21/n (No. 14)
20.287(4)
b, Å
18.878(4)
15.5787(14)
15.739(2)
c, Å
21.200(4)
22.468(3)
20.271(5)
R, deg
â, deg
γ, deg
V, Å3
105.11(3)
113.66(3)
90.36(3)
6563(2)
90
90
92.52(1)
90
6466(2)
91.405(17)
90
6607.3(14)
Z
d
4
4
4
calcd, g cm-3
1.519
1.544
1.508
T, K
173(2)
0.515
φ
50
173(2)
0.444
φ
50
193(2)
0.443
ω/θ
50
µ, mm-1
scan method
2θ(max), deg
total no. of rflns
51560
62685
11694
no. of unique rflns
no. of obsd rflns (I > 2σ(I))
no. of rflns used for refinement
no. of params refined
final R indices (I > 2σ(I))
R indices (all data)
resid electron density, e A-3
21786 [R(int) ) 0.0639]
11647 [R(int) ) 0.0701]
11351 [R(int) ) 0.0325]
11 834
7096
6414
21786
1879
11647
972
11351
877
R1 ) 0.0460, wR2 ) 0.1032a
R1 ) 0.0931, wR2 ) 0.1152a
1.213/-0.912
R1 ) 0.0470, wR2 ) 0.1121a
R1 ) 0.0825, wR2 ) 0.1270a
0.633/-1.108
R1 ) 0.0678, wR2 ) 0.1293a
R1 ) 0.1377, wR2 ) 0.1649a
0.585/-0.508
w ) 1/[σ2(Fo2) + (0.0585P)2 + 0.0000P] (2b‚1/2CH2Cl2), w ) 1/[σ2(Fo2) + (0.0797P)2 + 0.0000P] (5e), w ) 1/[σ2(Fo2) + (0.0451P)2
+
a
15.0489P] (6a ), where P ) [Fo + 2Fc2]/3.
2
P r ep a r a tion of [Ru Cl{dC(CH2P h )OC(O)C6H3(NO2)2-
2,4}(P iP r 3)2]BAr f (6j). This complex was prepared as de-
scribed for 6c, starting from 3j (105 mg, 0.14 mmol) and
[H(OEt2)2]BArf (134 mg, 0.13 mmol). Olive-green microcrys-
talline solid: yield 199 mg (92%); mp 107 °C dec. The NMR
data indicated that in solution (CD2Cl2) both isomers 6j
and 5j (molar ratio ca. 2:1) are present. Anal. Calcd for
C65H64BClF24N2O6P2Ru: C, 47.77; H, 3.95; N, 1.71. Found: C,
47.60; H, 3.85; N, 1.69. 1H NMR (400 MHz, CD2Cl2, 223 K): δ
173.6 (br t, CHF2CO2), 130.4, 129.9, 129.0, 128.6 (all s, C6H5),
104.5 (br t, CHF2CO2), 57.6 (s, CH2Ph), 24.1 (vt, N ) 10.2 Hz,
PCHCH3), 18.7 (s, PCHCH3). 31P{1H} NMR (81.0 MHz,
CD2Cl2): δ 45.9 (s). 19F{1H} NMR (188.3 MHz, CD2Cl2): δ
-63.2 (s, 24F, CF3 of Arf), -124.9 (s, 4F, CHF2).
P r ep a r a tion of [Ru (κ2-O2CCF 3){dC(CH2P h )OC(O)CF 3}-
(P iP r 3)2]BAr f (7b). This compound was prepared and purified
as described for 5e, starting from 4b (185 mg, 0.25 mmol) and
[H(OEt2)2]BArf (240 mg, 0.24 mmol). Pale yellow crystals: yield
319 mg (83%); mp 108 °C dec. Anal. Calcd for C62H61BF30O4P2-
Ru: C, 46.14; H, 3.81. Found: C, 45.86; H, 3.73. IR (Nujol):
ν(CdO) 1691 cm-1. 1H NMR (400 MHz, CD2Cl2, 253 K): δ 7.75
(br m, 8H, ortho-H of Arf), 7.58 (br m, 4H, para-H of Arf), 7.46
(m, 5H, C6H5), 5.27 (s, 2H, CH2Ph), 2.18 (br m, 6H, PCHCH3),
4
8.64 (d, J HH ) 2.0 Hz, 0.65H, H3 of C6H3 for 6j), 8.58 (dd,
4
3J HH ) 8.5, J HH ) 2.0 Hz, 0.65H, H5 of C6H3 for 6j), 8.50 (dd,
4
3J HH ) 8.5, J HH ) 2.0 Hz, 0.35H, H5 of C6H3 for 5j), 8.39 (d,
3
4J HH ) 2.0 Hz, 0.35H, H3 of C6H3 for 5j), 8.32 (d, J HH ) 8.5,
3
0.35H, H6 of C6H3 for 5j), 8.15 (d, J HH ) 8.5, 0.65H, H6 of
3
C6H3 for 6j), 7.72 (s, 8H, ortho-H of Arf), 7.53 (s, 4H, para-H
of Arf), 7.41 (m, 5H, C6H5), 5.05 (s, 1.3H, CH2Ph of 6j), 4.54 (s,
0.7H, CH2Ph of 5j), 2.50 (br m, 2.1H, PCHCH3 of 5j), 2.34 (br
1.25 (dvt, N ) 15.3, J HH ) 7.3 Hz, 36H, PCHCH3). 13C{1H}
2
NMR (100.6 MHz, CD2Cl2, 253 K): δ 331.0 (t, J PC ) 5.7 Hz,
1
RudC), 130.3, 130.2, 130.0, 126.7 (all s, C6H5), 113.3 (q, J FC
3
m, 3.9H, PCHCH3 of 6j), 1.30 (dvt, N ) 14.6, J HH ) 7.0 Hz,
) 287.2 Hz, CF3CO2), 65.4 (s, CH2Ph), 25.2 (vt, N ) 10.2 Hz,
PCHCH3), 18.9 (s, PCHCH3), signal of CF3CO2 not observed.
31P{1H} NMR (162.0 MHz, CD2Cl2, 253 K): δ 56.5 (s). 19F NMR
(376.4 MHz, CD2Cl2, 253 K): δ -62.6 (s, 24F, CF3 of Arf), -73.4
(br s, 6F, CF3CO2).
11.7H, PCHCH3 of 6j), 1.23 (m, 12.6H, PCHCH3 of 5j), 1.09
(dvt, N ) 14.4, 3J HH ) 7.4 Hz, 11.7H, PCHCH3 of 6j). 13C NMR
(100.3 MHz, CD2Cl2, 243 K): δ 330.8 (br m, RutC of 5j), 284.5
(br m, RudC of 6j), 173.6, 172.8 (both s, C6H3CO2 of 5j and
6j), 151.8, 150.7, 150.5, 150.2 (all br s, C2 and C4 of C6H3 for
5j and 6j), 134.3, 133.1, 131.3, 130.3, 130.0, 129.0, 128.6, 127.6,
125.9, 118.8, 117.9 (all s or br s, C6H5 and C1, C3, C5, C6 of
C6H3 for 5j and 6j), 64.2 (s, CH2Ph of 5j), 60.7 (s, CH2Ph of
6j), 25.1 (br m, PCHCH3 of 5j), 23.6 (vt, N ) 10.2 Hz, PCHCH3
of 6j), 19.9, 19.0 (both s, PCHCH3 of 5j), 19.1, 18.6 (both s,
PCHCH3 of 6j). 31P{1H} NMR (162.0 MHz, CD2Cl2, 223 K): δ
50.2 (br s, 5j), 49.4 (s, 6j).
P r ep a r a tion of [Ru (K2-O2CCF 3){dC(CH2P h )OC(O)H}-
(P iP r 3)2]BAr f (7c). This complex was prepared and purified
as described for 5e, starting from 4c (102 mg, 0.15 mmol) and
[H(OEt2)2]BArf (151 mg, 0.15 mmol). Orange solid: yield 175
mg (75%); mp 84 °C dec. Anal. Calcd for C61H62BF27O4P2Ru:
1
C, 47.39; H, 4.04. Found: C, 47.16, 3.97. H NMR (200 MHz,
CDCl3): 8.05 (s, 1H, HCO2), 7.70 (br m, 8H, ortho-H of Arf),
7.52 (br m, 4H, para-H of Arf), 7.43 (m, 5H, C6H5), 5.04 (s, 2H,
P r ep a r a tion of [Ru (K2-O2CCHF 2){dC(CH2P h )OC(O)-
CHF 2}(P iP r 3)2]BAr f (7a ). This complex was prepared as
described for 6c, starting from 4a (235 mg, 0.33 mmol) and
[H(OEt2)2]BArf (327 mg, 0.32 mmol). Orange solid: yield 505
mg (99%); mp 52 °C dec. Anal. Calcd for C62H63BClF28O4P2-
Ru: C, 47.19; H, 4.02. Found: C, 46.75; H, 4.07. IR (Nujol):
CH2Ph), 1.97 (m, 6H, PCHCH3), 1.16 (dvt, N ) 14.1, J HH
)
3
3
7.1 Hz, 18H, PCHCH3), 1.15 (dvt, N ) 14.8, J HH ) 7.1 Hz,
18H, PCHCH3). 13C{1H} NMR (50.3 MHz, CDCl3, 253 K): δ
2
295.4 (t, J PC ) 5.1 Hz, RudC), 172.2 (s, HCO2), 165.7 (q,
2J FC ) 39.4 Hz, CF3CO2), 130.5, 129.9, 128.9, 128.6 (all s,
1
C6H5), 112.7 (q, J FC ) 284.7 Hz, CF3CO2), 64.4 (s, CH2Ph),
ν(CdO) 1638, νas(OCO) 1591 cm-1
.
1H NMR (200 MHz,
24.0 (vt, N ) 10.2 Hz, PCHCH3), 19.1, 18.4 (both s, PCHCH3).
31P{1H} NMR (81.0 MHz, CDCl3): δ 44.0 (s). 19F NMR
(188.3 MHz, CDCl3): δ -62.8 (s, 24F, CF3 of Arf), -75.3 (s,
3F, CF3CO2).
ROMP of Cycloocten e w ith Com p lexes 2a -d a s Ca ta -
lyst P r ecu r sor s. A sample of 2a -d (6 µmol) was dissolved
CD2Cl2): δ 7.73 (br m, 8H, ortho-H of Arf), 7.57 (br m, 4H,
2
para-H of Arf), 7.45 (m, 5H, C6H5), 6.15 (t, J HF ) 52.2 Hz,
2H, CHF2), 5.07 (s, 2H, CH2Ph), 2.04 (m, 6H, PCHCH3), 1.19
3
(dvt, N ) 14.6, J HH ) 7.3 Hz, 36H, PCHCH3). 13C{1H} NMR
2
(50.3 MHz, CD2Cl2, 243 K): δ 296.1 (t, J PC ) 5.1 Hz, RudC),

Carbene and Carbyne Ruthenium Complexes
Organometallics, Vol. 20, No. 17, 2001 3685
in CD2Cl2 (550 µL) and treated in an NMR tube with cy-
clooctene (0.6 mmol, 100 equiv). The polymerization was
followed by 1H NMR spectroscopy. Total consumption of the
monomer was observed after 20 h with 2a and 2b as precata-
lyst, and the reaction was accompanied by the formation of a
brownish viscous solution. The 13C NMR spectra of the
polymers revealed with regard to the configuration at the
double bonds a trans/cis ratio of 78:22 (2a ) or 73:27 (2b). In
the case of 2c and 2d , a conversion of only 50 or 10%,
respectively, of cyclooctene to the polymer was observed.
X-r a y Str u ctu r a l An a lysis of 2b‚1/2CH2Cl2, 5e a n d 6a .
Single crystals of 2b‚1/2CH2Cl2 and 5e were grown from
dichloromethane at -20 °C, and those of 6a from chloroform
at -20 °C. The data were collected from a shock-cooled crystal
protected by an oil drop on a Stoe IPDS diffractometer (2b‚1/
2CH2Cl2, 5e) or an Enraf-Nonius CAD4 diffractometer (6a )
using monochromated Mo KR radiation (λ ) 0.71073 Å).
Crystal data collection parameters are summarized in Table
2. Intensity data were corrected by Lorentz and polarization
effects, and for 6a an Lp and empirical absorption correction
were applied (Ψ-scan method, minimum transmission 91.35%).
The structure of 2b‚1/2CH2Cl2 was solved by direct methods,
and the structures of 5e and 6a were solved by the Patterson
method (SHELXS-97).26 Atomic coordinates and anisotropic
displacement parameters were refined by full matrix least-
(DELU, SIMU) and occupancy factors 50:50; also eight of the
CF3 groups of the BArf anions of 2b‚1/2CH2Cl2 were found
rotationally disordered and refined in the same way with the
following occupancy factors: 69:40 (F1-F3), 83:17 (F7-F9),
75:25 (F16-F18), 80:20 (F7A-F9A), 50:50 (F10A-F12A), 80:
20 (F13A-F16A), 85:15 (F16A-F18A), 65:35 (F19A-F21A).
The CF3 group of the trifluoroacetato ligand of 5e and three
of the CF3 substituents on the BArf anion were also found
rotationally disordered with the occupancy factors 78:22 (F25-
F27), 66:36 (F4-F6), 78:22 (F7-F9), and 56:44 (F22-F24). The
hydrogen atoms H2A, H2B, and H9 of 6a were found in a
differential Fourier synthesis and refined isotropically by
setting the displacement parameter to 120% of the equivalent
isotropic U value of C2 and C9; one CF3 group of the BArf anion
of 6a was found rotationally disordered with occupancy factors
of 80:20 (F16-F18).
Ack n ow led gm en t. This work was supported by the
European Commission under the Training and Mobility
of Researchers program (Marie Curie Fellowship to
P.G.-H., contract No. ERBFMBICT972450), the Deut-
sche Forschungsgemeinschaft (Grant SFB 347), and the
Fonds der Chemischen Industrie. We gratefully ac-
knowledge support by Mrs. R. Schedl and Mr. C. P.
Kneis (DTA and elemental analysis), Mrs. M.-L. Scha¨-
fer, and Dr. W. Buchner (NMR measurements).
squares against F0 (SHELXL-97).27 The CH2Cl2 molecule in
2
2b‚1/2CH2Cl2 was found disordered over two independent
positions and refined anisotropically with restraints on U(ij)
Su p p or tin g In for m a tion Ava ila ble: Tables of crystal
data and refinement parameters, bond lengths and angles, and
positional and thermal parameters for 2b. This material is
available free of charge via the Internet at http://pubs.acs.org.
(25) Brookhart, M.; Grant, B.; Volpe, A. F. Organometallics 1992,
11, 3920-3922.
(26) Sheldrick, G. M. Acta Crystallogr. Sect. A 1990, 46, 467-473.
(27) Sheldrick, G. M. SHELXL-97; University of Go¨ttingen: Go¨t-
tingen, Germany, 1997.
OM010422X