[CpRu(η6-naphthalene)]PF6 as precursor in complex synthesis and catalysis with the cyclopentadienyl-ruthenium(II) cation

Article abstract of DOI:10.1021/om900333t

The complex [CpRu(η⁶-naphthalene)]PF6 (2) is a readily accessible and air-stable source of the CpRu⁺ fragment (Cp = η⁵C₅H₅) for applications in complex synthesis and catalysis. The utility of this pre

Full text of DOI:10.1021/om900333t

Organometallics 2009, 28, 5739–5748 5739
DOI: 10.1021/om900333t
[CpRu(η6-naphthalene)]PF6 as Precursor in Complex Synthesis and
Catalysis with the Cyclopentadienyl-Ruthenium(II) Cation
,‡
Lukas Hintermann,* Li Xiao, Aurelie Labonne, and Ulli Englert
§
ꢀ
Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52074 Aachen, Germany.
‡
€
€
New address: Department Chemie, Technische Universitat Munchen, Lichtenbergstrasse 4, 85747
Garching, Germany. §Institute of Inorganic Chemistry, RWTH Aachen University
Received April 28, 2009
The complex [CpRu(η6-naphthalene)]PF6 (2) is a readily accessible and air-stable source of the CpRuþ
fragment (Cp=η5-C5H5) for applications in complex synthesis and catalysis. The utility of this
precursor complex is demonstrated in a number of experiments: The counterion of 2 is exchanged by
reaction with cinchonidinium Δ-TRISPHAT to give [CpRu(η6-naphthalene)]Δ-TRISPHAT (4; with
X-ray crystal structure). Ligand exchange of 2 in acetonitrile with (Z,Z)-1,5-cyclooctadiene (COD)
produces [CpRu(η2:η2-COD)(MeCN)]PF6 (5; with X-ray crystal structure); with chelating phosphanes
(P-P), complexes [CpRu(P-P)(MeCN)]PF6 are selectively generated, and starting with a 1,4-diaza-
diene, a solvento complex [CpRu(diazadiene-N,N0)(MeCN)]PF6 is obtained. Stepwise reaction of 2
(or 4) in acetonitrile with different monodentate phosphanes PR3 and PR03 fþirst gives [CpRu-
(PR3)(MeCN)2]þ (I), then the chiral-at-metal cation [CpRu(PR3)(PR03)(MeCN)] (II), which was
resolved spectroscopically (31P NMR) when combined with the enantiopure Δ-TRISPHAT counterion.
Complex cations of type I or II incorporating 2-diphenylphosphinopyridines as ligands display either the
η1-P or the chelating η2-P,N coordination mode, depending on the size of the ligand and, in solution, the
solvent. Reaction of 2 with 3 equiv of triarylphosphanes (PR3) in hot acetone gives rise to [CpRu-
(PR3)3]þ, including the previously unknown cation [CpRu(PPh3)3]þ. The in situ combination of 2 and 2
equiv of bulky 6-substituted 2-pyridylphosphanes catalyzes the anti-Markovnikov hydration of terminal
alkynes to aldehydes. Either complex 2 or 5 catalyzes the [2þ2þ2]-cycloaddition of COD with alkynes.
Complex 5 is a catalyst for the coupling of allyl alcohols with terminal alkynes to give 4-alkenones.
Introduction
because two of its acetonitrile ligands are displaced under
mild conditions, often in a stepwise manner. Recently, 1 has
been applied in the selective synthesis of monophosphane
complexes [CpRu(PR3)(MeCN)2]X,3,4,7-12 nonsymme-
trical complexes [CpRu(PR1 )(L)(MeCN)]X (L = PR2 or
The η5-cyclopentadienylruthenium(II) cation (CpRuþ; Cp
is η5-C5H5 throughout this work) displays a rich chemistry of
pseudotetrahedral [CpRu(L1)(L2)(L3)]þ cations or neutral
[CpRu(L1)(L2)X] complexes (Ln = neutral two-electron
donor; X = monoanionic group), which has been the source
of countless mechanistic and stereochemical studies or ap-
plications in organometallic catalysis.1,2 A popular synthetic
precursor in this chemistry is [CpRu(MeCN)3]PF6 (1),1,3-6
3
3
NR3),3,7,10,13,14 and symmetrical bis-phosphane complexes
[CpRu(PR3)2(MeCN)]X.15-17 Furthermore, monoisonitrile18
€
(7) Ruba, E.; Simanko, W.; Mauthner, K.; Soldouzi, K. M.; Slugovc,
C.; Mereiter, K.; Schmid, R.; Kirchner, K. Organometallics 1999, 18,
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(9) Standfest-Hauser, C. M.; Mereiter, K.; Schmid, R.; Kirchner, K.
Eur. J. Inorg. Chem. 2003, 1883.
(10) Grotjahn, D. B.; Larsen, C. R.; Gustafson, J. L.; Nair, R.;
Sharma, A. J. Am. Chem. Soc. 2007, 129, 9592.
(11) Osipov, A. L.; Gutsulyak, D. V.; Kuzmina, L. G.; Howard, J. A.
K.; Lemenovskii, D. A.; Suess-Fink, G.; Nikonov, G. I. J. Organomet.
Chem. 2007, 692, 5081.
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Soc. 2004, 126, 13632. (b) Kumagai, N.; Matsunaga, S.; Shibasaki, M.
Chem. Commun. 2005, 3600. (c) Kumagai, N.; Matsunaga, S.; Shibasaki, M.
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*Corresponding author.E-mail: lukas.hintermann@oc.rwth-aachen.de.
(1) (a) Gimeno, J; Cadierno, V.; Crochet, P. Comprehensive Organo-
metallic Chemistry III; Mingos, D. M. P.; Crabtree, R. H.; Bruce, M., Eds.;
Elsevier: Amsterdam, 2007; Vol. 6, p 465. (b) Bennett, M. A.; Khan, K.;
Wenger, E. Comprehensive Organometallic Chemistry II; Shriver, D. F.;
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M. A.; Bruce, M. I.; Matheson, T. W. Comprehensive Organometallic
Chemistry; Wilkinson, G. Ed.; Pergamon: Oxford, U.K., 1982; Vol. 4,
p 775. (d) Davies, S. G.; McNally, J. P.; Smallridge, A. J. Adv. Organomet.
Chem. 1990, 30, 1.
(2) (a) Trost, B. M.; Frederiksen, M. U.; Rudd, M. T. Angew. Chem.
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Acc. Chem. Res. 2002, 35, 695.
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Chem., Int. Ed. 2006, 45, 1599.
€
(3) Slugovc, C.; Ruba, E.; Schmid, R.; Kirchner, K.; Mereiter, K.
(14) Slugovc, C.; Simanko, W.; Mereiter, K.; Schmid, R.; Kirchner,
K.; Xiao, L.; Weissensteiner, W. Organometallics 1999, 18, 3865.
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B. M.; Older, C. M. Organometallics 2002, 21, 2544.
(5) Trost, B. M.; Older, C. M. Organometallics 2002, 21, 2544.
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r
2009 American Chemical Society
Published on Web 09/08/2009
pubs.acs.org/Organometallics

5740 Organometallics, Vol. 28, No. 19, 2009
Hintermann et al.
or -carbene19 complexes [CpRu(L)(MeCN)2]X have been pre-
pared. The high reactivity of 1 has also provided easy access to
cations [CpRu(N-N)(MeCN)]þ with N-N = diamines,4 di-
imines,9,20,21 or bipyridines,21 which are not readily prepared
from CpRu(PPh3)2Cl. For a long time, the preparation of 1
itself has been relatively involved and has relied on the use of
toxic reagents (TlC5H4) and photochemical equipment.4,5 Im-
proved syntheses of 1 have recently been reported.5,6 The
6
€
Kundig route is a particular improvement: it starts from
RuCl3 and leads, via RuCp2 and [CpRu(η6-naphthalene)]PF6
(2), to 1.6,22 In recent work on ruthenium-catalyzed anti-
Markovnikov hydration of terminal alkynes, we have used
complex 2, rather than 1, to prepare the catalysts [CpRu-
(PR3)2(MeCN)]PF6 in situ by ligand exchange with several
pyridyl-phosphanes.23-25 We proposed that the air- and moist-
ure-tolerant complex [CpRu(naphthalene)]PF6 (2) can be an
advantageous starting material for complex synthesis and
catalysis with CpRuþ, which may replace 1 (which is moist-
ure-sensitive and has a limited shelf life) in many applications.23
Now, we support this proposal by reporting on uses of 2 in the
synthesis of cationic ruthenium complexes with olefin, diaza-
diene, and phosphane ligands and as a catalyst precursor in
alkyne hydration, [2þ2þ2]-cycloaddition, or alkene/alkyne
coupling reactions.26 Several advantages of the use of 2 have
been identified, namely, (i) its availability and air-stability,
(ii) its ready exchange of the counterion in aqueous biphasic
reaction media, allowing for a simple entry into chiral enantio-
pure counterion chemistry, and (iii) the option to perform
ligand exchanges at the CpRuþ fragment in the absence of
acetonitrile. These advantages outweigh the necessity for long-
er reaction times or higher temperatures relative to reactions
with 1 that are sometimes needed.
Figure 1. X-ray crystal structure of [CpRu(η6-naphthalene)]Δ-
TRISPHAT CH2Cl2 (4 CH2Cl2). Ellipsoid plots are drawn at
the 50% probability level. The molecular structure of one
independent cation and anion each is shown, but the solvent
of crystallization is omitted. Hydrogen atoms are shown with
3
3
˚
arbitrary radius. Selected interatomic distances (A) and angles
(deg): Ru2-C20 2.199(3), Ru2-C17 2.210(3), Ru2-C19
2.211(3), Ru2-C18 2.216(3), Ru2-C21 2.273(3), Ru2-C16
2.281(3), P2-O7 1.7081(17), P2-O12 1.7099(17), P2-O11
1.7112(16), P2-O9, 1.7135(17), P2-O8 1.7157(16), P2-O10
1.7202(16), O7-P2-O9 179.14(9), O12-P2-O8 179.23(9),
O11-P2-O10 179.01(9), C20-Ru2-C17 79.10(10).
Scheme 1. Ion Exchange Reaction of 2 with Cinchonidinium
Δ-TRISPHAT (3)
Results and Discussion
Counterion Exchange. The complex cation [CpRu(η6-
naphthalene)]þ is already available with a range of counter-
ions.6 We have extended this range to include a chiral
enantiopure counterion: reaction of 2 with cinchonidinium
(17) (a) Mebi, C. A.; Frost, B. J. Organometallics 2005, 24, 2339.
(b) Bolano, S.; Gonsalvi, L.; Zanobini, F.; Vizza, F.; Bertolasi, V.; Romerosa,
A.; Peruzzini, M. J. Mol. Catal. A 2004, 224, 61.
(18) Seidel, W. W.; Meel, M. J.; Radius, U.; Schaffrath, M.; Pape, T.
Inorg. Chem. 2007, 46, 9616.
(19) (a) Becker, E.; Stingl, V.; Dazinger, G.; Mereiter, K.; Kirchner,
K. Organometallics 2007, 26, 1531. (b) Becker, E.; Stingl, V.; Mereiter, K.;
Kirchner, K. Organometallics 2006, 25, 4166. (c) Becker, E.; Stingl, V.;
Dazinger, G.; Puchberger, M.; Mereiter, K.; Kirchner, K. J. Am. Chem. Soc.
2006, 128, 6572.
(20) (a) Gomez, J.; Garcia-Herbosa, G.; Cuevas, J. V.; Arnaiz, A.;
Carbayo, A.; Munoz, A.; Falvello, L.; Fanwick, P. E. Inorg. Chem. 2006,
45, 2483. (b) Govindaswamy, P.; Mozharivskyj, Y. A.; Kollipara, M. R.
Polyhedron 2004, 23, 1567.
Δ-TRISPHAT (3)27 proceeds in a two-phase aqueous/or-
ganic solvent system, where the oganometallic ion-pair
remains in the organic phase. After a filtration through
aluminum oxide, [CpRu(η6-naphthalene)]Δ-TRISPHAT
(4) is obtained in high yield (Scheme 1).
Compound 4 crystallized as a solvate with dichloro-
methane. The X-ray crystal structure is the first including a
[CpRu(naphthalene)]þ cation (Figure 1, Table 1). The unit
cell contains two symmetrically independent cations and
€
(21) (a) Constant, S.; Tortoioli, S.; Muller, J.; Lacour, J. Angew.
Chem. 2007, 119, 2128. Angew. Chem., Int. Ed. 2007, 46, 2082.
(b) Constant, S.; Tortoioli, S.; Mueller, J.; Linder, D.; Buron, F.; Lacour, J.
Angew. Chem. 2007, 119, 9137. Angew. Chem., Int. Ed. 2007, 46, 8979.
(22) (a) McNair, A. M.; Mann, K. R. Inorg. Chem. 1986, 25, 2519.
(b) Glatzhofer, D. T.; Liang, Y.; Funkhouser, G. P.; Khan, M. A. Organo-
metallics 1994, 13, 315. (c) Vol'kenau, N. A.; Bolesova, I. N.; Shul'pina, L. S.;
Kitaigorodskii, A. N.; Kravtsov, D. N. J. Organomet. Chem. 1985, 288, 341.
(23) Labonne, A.; Kribber, T.; Hintermann, L. Org. Lett. 2006, 8,
5853.
(24) Kribber, T.; Labonne, A.; Hintermann, L. Synthesis 2007, 2809.
(25) Labonne, A.; Zani, L.; Hintermann, L.; Bolm, C. J. Org. Chem.
2007, 72, 5704.
(26) Since our communication, 2 has also been used as catalyst
precursor by Lacour and co-workers: Linder, D.; Buron, F.; Constant,
S.; Lacour, J. Eur. J. Org. Chem. 2008, 5778.
(27) (a) Favarger, F.; Goujon-Ginglinger, C.; Monchaud, D.;
Lacour, J. J. Org. Chem. 2004, 69, 8521. (b) Jodry, J. J. Interactions
ꢀ
Asymetriques entre Cations et Anions Chiraux. Doctoral Thesis, University
of Geneva: Geneva, 2000. (c) Lacour, J.; Ginglinger, C.; Grivet, C.;
Bernardinelli, G. Angew. Chem. 1997, 109, 660. Angew. Chem., Int. Ed.
Engl. 1997, 36, 608.

Article
Table 1. Crystallographic Data for 4 CH2Cl2 and 5
Organometallics, Vol. 28, No. 19, 2009 5741
3
4 CH2Cl2
3
5
empirical formula
fw
C34H15Cl14O6PRu
1147.80
C15H20F6NPRu
460.36
cryst size (mm)
cryst habit
cryst syst
0.45 ꢀ 0.40 ꢀ 0.16
plate, yellow
monoclinic
P21
10.1227(10)
20.0704(19)
20.0116(19)
99.168(2)
4013.8(7)
1.899
4
130(2)
2256
0.570-0.806
2.04-31.24
-14 e h e 14
-28 e k e 29
-28 e l e 28
58 992
0.44 ꢀ 0.21 ꢀ 0.19
rod, orange
orthorhombic
Pna21
15.4248(14)
14.9326(14)
7.1632(7)
90
1649.9(3)
1.853
4
130(2)
920
0.642-0.817
2.64-32.17
-22 e h e 21
-20 e k e 20
-10 e l e 10
24 054
space group
˚
a (A)
˚
b (A)
˚
c (A)
β (deg)
3
V (A )
˚
F
calc (g cm-3
)
Z
T (K)
F(000)
min./max. transmn
θ range (deg)
index ranges
Figure 2. X-ray crystal structure of 5 (counterion omitted).
ORTEP plot with 50% probability ellipsoids. Hydrogen atoms
are shown with arbitrary radius. Selected interatomic distances
no. of rflns measd
no. of unique rflns
Rint
23 197
0.0273
5065
0.0301
˚
(A) and angles (deg): Ru1-N1 2.0792(18), Ru1-C13
2.2508(19), Ru1-C9 2.255(2), Ru1-C12 2.2609(19), Ru1-C8
2.274(2), N1-C1 1.131(3), C1-C2 1.463(3), C8-C9 1.378(3),
C12-C13 1.382(3), C13-Ru1-C9 93.02(8), C12-Ru1-C8
84.66(7).
no. of params
R1 (2σ(I))
R1 (all data)
wR2 (all data)
Flack param
goodness of fit
1009
0.0286
0.0316
0.0662
-0.023(12)
1.030
1.136/-0.551
219
0.0242
0.0259
0.0582
0.46(3)
1.075
1.210/-0.367
directly by stirring of 2 with COD and LiCl in acetonitrile
were not successful. After addition of an excess of trimethyl-
chlorosilane to a solution of 5 in acetone-d6, 1H NMR signals
of the desired chloro complex 6 were detected,29 but the
reaction was incomplete and no satisfactory preparative
procedure could be devised. Ligand exchange reactions of
2 with several chelating diphosphine ligands including 1,2-
bis-diphenylphosphinoethane (dppe), (R)-(þ)-BINAP, or
(1R,SP)-Josiphos30 gave the cationic solvento complexes
7a,31 7b,32 and 7c (the latter as a mixture of diastereomers)
in high yields (Scheme 3). An earlier synthesis of 7a (56%
yield) from [CpRu(MeCN)3]PF6 (1) and dppe suffered from
side-reactions giving dinuclear products,31 and a previous
synthesis of 7b from CpRuCl(BINAP) and AgPF6 gave the
product in 44% yield.32 As reported, 7b equilibrates with
desolvated [CpRu(η1:η3-BINAP)]PF6.32 The complex synth-
eses starting from 2 and chelating ligands offer advantages in
view of the high yields and the simple purification procedure,
which simply consists in washing away of the naphthalene
side-product with hexanes. This protocol was further ex-
tended to obtain the new diazadiene-N,N0 complex 8 in high
yield from 2 and 1,4-bis(2,6-diisopropylphenyl)-1,4-diaza-
butadiene33 (Scheme 3).
3
˚
diff peak/hole (e/A )
Scheme 2. Ligand Exchange of 2 with COD
anions with largely identical geometrical parameters. The η6-
bonding of ruthenium to naphthalene is slightly asymmetric,
with Ru-C bond lengths of 2.20-2.21 A to the naphthalene
R-carbons, 2.21-2.22 A to the β-carbons, but 2.27-2.28 A
to the quaternary carbons.
˚
˚
˚
Ligand Exchange Reactions. An acetonitrile solution of
[CpRu(η6-naphthalene)]PF6 (2) containing a small excess of
(Z,Z)-1,5-cyclooctadiene (COD) was stirred overnight to
give the complex [CpRu(η2:η2-COD)(MeCN)]PF6 (5)28 as
a crystalline and air-stable material in high yield, after
evaporation and recrystallization (Scheme 2). The monitor-
ing of the ligand exchange at room temperature by 1H NMR
showed that the conversion reached 50% after 3 h and was
essentially completed after 30 h. In acetone, less than 5%
conversion occurred after 2 days at room temperature,
pointing to the important role of the acetonitrile solvent to
accelerate the ligand exchange reaction. The crystal structure
analysis of 5 shows that the coordination around ruthenium
can be interpreted as tetrahedral if Cp is considered a
univalent ligand, thus resulting in a three-legged piano stool
geometry.
Coordination Chemistry of the CpRuþ Fragment with Pyr-
idylphosphanes. The stirring of 2 with 1 equiv of 6-(2,4,6-
triphenylphenyl)-2-diphenylphospinopyridine (2,4,6Ph3C6H2-
PyPPh2) (9)23,34 in acetonitrile at room temperature overnight
forms [CpRu(η1-9)(MeCN)2]PF6 (10) as the sole detectable
(30) Togni, A.; Breutel, A.; Schnyder, A.; Spindler, F.; Landert, H.;
Tijani, A. J. Am. Chem. Soc. 1994, 116, 4062.
(31) Di Vaira, M.; Costantini, S. S.; Mani, F.; Peruzzini, M.;
Stoppioni, P. J. Organomet. Chem. 2004, 689, 1757.
(32) Anil Kumar, P. G.; Pregosin, P. S.; Vallet, M.; Bernardinelli, G.;
Attempts to prepare the neutral complex CpRuCl(η2:η2-
COD) (6)29 by reaction of 5 with LiCl in MeOH at reflux or
€
Jazzar, R. F.; Viton, F.; Kundig, E. P. Organometallics 2004, 23, 5410.
(33) (a) Hintermann, L. Beilstein J. Org. Chem. 2007, 3, 22.
(b) Jafarpour, L.; Stevens, E. D.; Nolan, S. P. J. Organomet. Chem. 2000,
606, 49.
(34) Hintermann, L.; Dang, T. T.; Labonne, A.; Kribber, T.; Xiao,
L.; Naumov, P. Chem.-Eur. J. 2009, 15, 7167.
(28) Complex 5 has previously been obtained from 1 and COD:
see ref 7.
(29) Albers, M. O.; Robinson, D. J.; Shaver, A.; Singleton, E.
Organometallics 1986, 5, 2199.

5742 Organometallics, Vol. 28, No. 19, 2009
Hintermann et al.
Scheme 3. Reactions of 2 with Chelating Ligands
ligand 2-diphenylphosphinopyridine (14) can be expected
to show a higher tendency toward chelation. Nevertheless,
exchange of [CpRu(η6-naphthalene)]PF6 (2) with a single
equivalent of 2-diphenylphosphinopyridine (14; δ{31P} =
-4.3 ppm in acetonitrile-d3, δ = -3.9 ppm in CDCl3) in
acetonitrile solution produced a single dissolved species,
[CpRu(η1-14)(MeCN)2]PF6 (15) (>95% abundance; cf.
Table 2). After evaporation and dissolution of the sample
in acetone-d6, this had rearranged to the chelate [CpRu-
(η2-14)(MeCN)]PF6 (16) (>95% abundance) with a char-
acteristic low-frequency shift of the 31P NMR signal
(Table 2). The reaction of 2 with 2 equiv of 14 in acetonitrile
directly produced an equilibrium mixture of [CpRu(η1-14)2-
(MeCN)]PF6 (17; 44% abundance)35 and [CpRu(η1-14)-
(η2-14)]PF6 (18; 56% abundance).35 After evaporation and
redissolution in CDCl3, 18 remained as the only detected
species (>95% abundance).
A conflicting literature report concerning the coordi-
nation chemistry of phosphinopyridine 14 with the CpRuþ
fragment is available, based on NMR observation of
ligand exchange experiments:39 the reaction mixture of
[CpRu(MeCN)3]PF6 (1) and 2 equiv of 14 in CDCl3 was
reported to display signals at δ(31P) = 51.5 ppm (>90%
abundance), assigned to [CpRu(η1-14-κP)2(MeCN)]PF6
(i.e., our species 17) and a minor signal at δ(31P) = 0.35
ppm (<10%), speculatively assigned to the unusual40 nitro-
gen-coordinated [CpRu(η1-14-κN)2(MeCN)]PF6. These data
are at variance with ours (Table 2) and do not fit the
chemical shift value found for [CpRu(L)2(MeCN)]PF6 (L =
various 6-substituted 2-diphenylphosphinopyridines), which
is typically around δ = 43 ppm.23,41 Moreover, compari-
son with Table 2 implies that the reported39 values of δ =
51.5 and 0.35 ppm correspond to the monophosphane com-
plexes 15 and 16. To clarify the issue, we have repeated the
NMR experiment and find that stirring of 1 with 2 equiv of 14
in CDCl3 for 12 h gives clean 31P NMR signals for 18 as major
species (g95% abundance) and 17 as a minor component
(e5%; see Table 2 for δ-values). Apparently, the mixing ratios
used in the NMR experiment of ref 39 have been mistaken,
leading to incorrect assignments.
species in solution (Scheme 4). The 31P NMR spectrum shows
that the pyridylphosphane binds in a η1-fashion at phosphorus.
After evaporation and redissolution in acetone-d6, 10 (δ =
51.1 ppm, 65% abundance)35 equilibrates with the chelated
species [CpRu(η2-9)(MeCN)]PF6 (11; δ=0.1 ppm, 35%) and
uncomplexed acetonitrile. The latter complex displays the
characteristic low-frequency 31P NMR shift of phosphorus
donors in four-membered chelate rings.36 It is remarkable that
phosphinopyridine 9 forms a chelate, because this type of
ligand with a bulky group at pyridine-C6 has been designed
to favor the η1-binding mode of phosphorus,37 where the
noncomplexed nitrogen donor may undergo secondary inter-
actions. However, a comparable observation has been re-
ported by Grotjahn and co-workers, who found an equilibrium
between [CpRu(η1-tBuPyPMe2)2(H2O)]þ and [CpRu(η1-tBu-
PyPMe2)(η2-tBuPyPMe2)]þ (tBuPyPMe2 = 6-tert-butyl-2-di-
methylphosphinopyridine) in CD2Cl2 solution.38
In the reaction of 2 with 2 equiv of 9 (cf. Scheme 5),
complex [CpRu(η1-9)2(MeCN)]PF6 (12) eventually forms,
but substitution of the second acetonitrile ligand from inter-
mediate 10 requires over a day at ambient temperature. This
step was accelerated by heating to 60 °C overnight. Alter-
natively, the solution of 10 in acetonitrile was evaporated,
and the resulting monophosphine complex mixture 10/11
was combined with an equivalent of 9 in acetone as a less
coordinating solvent to bring about a fast second substitu-
tion. The counterion of 12 could be exchanged with
HNBu3-(()-TRISPHAT27 to give [CpRu(η1-9)2(MeCN)]-
(()-TRISPHAT (13), whose spectral characteristics were
similar to 12, showing a single 31P NMR signal for the cation
(12: δ = 43.2 ppm in acetonitrile-d3 or δ = 44.1 ppm in
CDCl3; 13: δ = 44.2 ppm in benzene-d6) in several solvents,
with no sign of chelation. The sterically less demanding
Synthesis of Heteroleptic Complexes. The kinetic differen-
tiation of the first and second substitution step at [CpRu(η6-
naphthalene)]PF6 (2) with phosphanes in acetonitrile solu-
tion implied that nonsymmetrical complex cations of the
type [CpRu(L1)(L2)(MeCN)]þ should result from sequential
t
substitution. Indeed, addition of BuPyPPh2 (19)37 to a
solution of 10/11 in acetone gave rise to the mixed complex
[CpRu(η1-9)(η1-19)(MeCN)]PF6 (20; Scheme 5) with signals
at δ(31P) = 42.6 and 44.4 ppm and a 2JP,P coupling constant
of 34.9 Hz (Figure 3a). On the basis of the established
pseudotetrahedral coordination geometry of [CpRu(L)3]þ,
heteroleptic cations [CpRu(L1)(L2)(L3)]þ must display me-
tal-centered chirality42 and occur in enantiomeric forms.
This was proven by performing a sequential substitution
starting from [CpRu(η6-naphthalene)]Δ-TRISPHAT (4) in
(39) van der Drift, R. C.; Gagliardo, M.; Kooijman, H.; Spek, A. L.;
Bouwman, E.; Drent, E. J. Organomet. Chem. 2005, 690, 1044.
(40) (a) Zhang, Z.-Z.; Cheng, H. Coord. Chem. Rev. 1996, 147, 1.
(b) Newkome, G. R. Chem. Rev. 1993, 93, 2067.
(41) Labonne, A. Novel Aza-Arylphosphane Ligands for Ruthenium-
Catalyzed Anti-Markovnikov Hydration of Terminal Alkynes. Doctoral
Thesis, RWTH Aachen University, Aachen, 2007.
(35) Abundances of equilibrating species can be concentration de-
pendent. The data given are representative for NMR sample concentra-
tions of 30-50 mg/mL.
(36) Garrou, P. E. Chem. Rev. 1981, 81, 229.
(37) Baur, J.; Jacobsen, H.; Burger, P.; Artus, G.; Berke, H.; Dahlen-
burg, L. Eur. J. Inorg. Chem. 2000, 1411.
(38) Grotjahn, D. B.; Miranda-Soto, V.; Kragulj, E. J.; Lev, D. A.;
Erdogan, G.; Zeng, X.; Cooksy, A. L. J. Am. Chem. Soc. 2008, 130, 20.
(42) Brunner, H. Angew. Chem. 1999, 111, 1248. Angew. Chem., Int.
Ed. 1999, 38, 1194.

Article
Organometallics, Vol. 28, No. 19, 2009 5743
Scheme 4. Coordination Chemistry of CpRuþ with Pyridylphosphanes
Scheme 5. Synthesis of Chiral-at-Metal Complexes
Table 2. 31P NMR Parameters of [CpRu(14)n(MeCN)m]þ
Cations
compounda
δ(31P), ppm JP,P, Hz
solvent
[CpRu(η1-14)(MeCN)2]PF6 (15) 50.4
MeCN-d3
Me2CO-d6
MeCN-d3
CDCl3
MeCN-d3
CDCl3
[CpRu(η2-14)(MeCN)]PF6 (16)
-0.5
[CpRu(η1-14)2(MeCN)]PF6 (17) 44.0
[CpRu(η1-14)2(MeCN)]PF6 (17) 44.4
Figure 3. 31P NMR spectra at 121 MHz of (a) 20 in CDCl3; (b)
22 in CDCl3; (c) 22 in C6D6.
[CpRu(η1-14)(η2-14)]PF6 (18)
[CpRu(η1-14)(η2-14)]PF6 (18)
50.6/-8.4
51.2/-8.2
38.3
38.2
Characterization of [CpRu(P{aryl}3)3]þ Cations. The li-
gand exchange reactions on 2 have so far been carried out
in acetonitrile solution. Acetonitrile is a relatively strong
donor, and because it is desirable to have access to
[CpRu(L)2(solvento)]þ complexes with weakly coordinating
solvents, we also tried to perform ligand exchange reactions
of 2 in less coordinating solvents, but under thermally more
forcing conditions. In an attempt to synthesize [CpRu(η1-
19)2(H2O)]PF6, 2 was heated to 60 °C in the presence of
a In the case of measurements performed in MeCN-d3, the values refer
to the MeCN-d3 solvate analogues.
acetonitrile with ligands 9 and 19, giving, via 21, the mixed
complex [CpRu(η1-9)(η1-19)(MeCN)]Δ-TRISPHAT (22)
(Scheme 5). Under the influence of the enantiopure counter-
ion, two sets of signals are observed by 31P NMR spectros-
copy, revealing the presence of enantiomeric cations in a
50:50 ratio (Figure 3b); solvents such as CDCl3 (Figure 3b)
or benzene-d6 achieve complete separation of signals for the
diastereomeric ion-pairs (Figure 3c).
t
2 equiv of BuPyPPh2 (19) in acetone and a little water for
3 days. However, crystals of the tris-phosphine complex
[CpRu(η1-19)3]PF6 (23) separated from the reaction solution

5744 Organometallics, Vol. 28, No. 19, 2009
Hintermann et al.
instead. The same complex was also obtained by heating 2
with 4 equiv of 19 in acetone to 90 °C in a pressure tube
overnight. The 31P NMR signal of this complex, at δ(31P) =
38.4 ppm, is at lower frequency than the corresponding
mono- (δ = 50.0 ppm) or diphosphine (δ = 43.6 ppm) sol-
vato complexes,41 and the Cp signal is characteristically high
at δ(1H) = 5.09 ppm (all data in CDCl3). Interestingly, re-
crystallization attempts of [CpRu(η1-19)2(MeCN)]OTf un-
der a variety of conditions had earlier been noted to give
crystals of [CpRu(η1-19)3]OTf.43,44 We still found it note-
worthy that [CpRu(P{aryl}3)3]X complexes with monoden-
tate triarylphosphanes are stable at all. Bruce and co-
workers, in their fundamental paper on the substitution
chemistry of CpRuCl(PPh3)2, had written, “Interestingly
we have been unable to isolate the cation [Ru(PPh3)3(η5-
C5H5)]þ from any reactions involving excess PPh3, and we
ascribe this to the difficulty of fitting three bulky PPh3
molecules [...] around the central atom.”45 The [CpRu-
(PPh3)3]þ cation has not yet been reported in the literature.
By heating [CpRu(η6-naphthalene)]Δ-TRISPHAT (4) with
a slight excess of triphenylphosphine in acetone at 90 °C,
we obtained the tris-substituted species [CpRu(PPh3)3]Δ-
TRISPHAT (24) with a phosphorus NMR signal at δ =
32.4 ppm (in CD2Cl2) for the complex cation. The compound
decomposes in CDCl3 and partially dissociates in coordinat-
ing solvents to give [CpRu(PPh3)2(solvento)]þ species, e.g.,
with δ = 40.5 ppm (in acetone-d6). The hexafluoropho-
sphate salt [CpRu(PPh3)3]PF6, δ = 32.6 ppm (acetone-d6), is
prepared similarly, but could not be readily purified due to its
sensitivity and amorphous nature. There is a gradual de-
crease of the phosphorus NMR chemical shift on going
from [CpRu(PPh3)(MeCN)2]PF6, δ = 51.7 ppm in CDCl3,7
or δ = 50.8 ppm in acetone-d6,12c,46 to [CpRu(PPh3)2-
(MeCN)]PF6 with δ = 42.5 ppm in CDCl3,12b or 41.9 ppm
in acetone-d6,47 to the tris-phosphane cation with δ= 32.6 ppm
in acetone-d6.
Table 4. Ruthenium-Catalyzed [2þ2þ2]-Cycloaddition
entry
catalyst
mol %
T, °C
time, h
yield, %
1
2
3
4
5
5
5
5
5
2
5
1
2
5
5
70
70
70
rt
2
10
1
10
36
90
68
93
89
90
70
Table 5. Ruthenium-Catalyzed Alkyne/Allyl Alcohol Coupling
entry loading, mol % ratio 28/27 solvent T, °C time, h yield, %
1
2
3
4
5
5
5
5
5
5
3
3
3
2
2
DMF/H2O 90
DMF/H2O rt
THF/H2O 70
1
19
6
19
19
59
59
39
10
0
THF
acetone
rt
rt
fascinating tricyclic products such as 26.48 The original
reaction conditions asked for heating of the reactants with
5 mol % of CpRuCl(COD) in methanol for unspecified
reaction times.48 The results in Table 4 show that complex
5 performs favorably under these conditions (entries 1-3);
the catalyst loading can be reduced to 2 mol %, still getting a
near-optimal performance (entry 3).
The reaction even proceeded at room temperature (entry
4), reinforcing the assumption that 5 is an activated cata-
lyst precursor superior to CpRuCl(COD). Interestingly,
[CpRu(η6-naphthalene)]PF6 (2) was also a catalyst precur-
sor, but it requires prolonged reaction times, presumably as a
consequence of the slow release of naphthalene from 2 in
methanol. Complex 5 was used in another reaction that the
Trost group had originally catalyzed with CpRuCl(COD):49
the coupling of propargyl alcohol 27 with 3-buten-2-ol (28)
in water/N,N-dimethyl formamide solution at 90 °C with 5
mol % of catalyst gave a 60% yield of keto alcohol 29 after
2.5 h. The results in Table 5 show that cationic complex 5 is
again a valid replacement for CpRuCl(COD) (entries 1, 2),
although the coupling remains a difficult one in terms of the
yield and choice of solvent (entries 3-5). Notably, the high
reactivity of 5 allowed us to perform the reaction at room
temperature with no reduction in yield (entry 2).
Catalysis with [CpRu(η6-naphthalene)]PF6 (2) and [CpRu-
(η2:η2-COD)(MeCN)]PF6 (5) as Precursor Complexes. Trost
and co-workers have catalyzed a range of C-C bond form-
ing reactions with complex CpRuCl(PPh3)2 or CpRuCl-
(COD), often in the presence cocatalytic amounts of
NH4PF6 or Lewis acids.2 Assuming that the co-catalysts
assist in the ionization of the neutral precursor complexes to
give cationic species, we expected that the complex
[CpRu(η2:η2-COD)(MeCN)]PF6 (5) should be an activated
catalyst with no need for co-catalytic additives. To test this
hypothesis, we have investigated the ruthenium-catalyzed
[2þ2þ2]-cycloaddition of (Z,Z)-1,5-cyclooctadiene with
alkynes (1,4-diacetoxy-2-butyne 25, in this instance) to give
(43) Grotjahn, D. B.; Lev, D. A. J. Am. Chem. Soc. 2004, 126, 12232,
and Supporting Information.
(44) The Supporting Information of ref 43 gives δ(31P) =56.2 ppm
(CDCl3) for [CpRu(tBuPyPPh2)3]OTf, but this is presumably a clerical
error.
(45) Ashby, G. S.; Bruce, M. I.; Tomkins, I. B.; Wallis, R. C. Aust. J.
Chem. 1979, 32, 1003.
(46) Ref 39 reports δ(31P) =51.5 ppm for what was presumed to be
[CpRu(PPh3)2(MeCN)]PF6, which was prepared in situ from 1 and 2
equiv of PPh3 in CDCl3. As the measured value perfectly fits the
monophosphino complex, this reinforces our assumption that a sys-
tematic weighing error has occurred in that work.
Wehaveearlier reportedonthe catalytic anti-Markovnikov
hydration of terminal alkynes by means of [CpRu(L)2-
(MeCN)]PF6 complexes, which had been obtained from
[CpRu(η6-naphthalene)]PF6 (2) and 2 equiv of azaaryl-
phosphanes34 L (typically 19 or 9) in hot acetonitrile.23 Since
(47) We prepared a reference sample of [CpRu(PPh3)2(MeCN)]PF6
by stirring 2 with 2 equiv of PPh3 in MeCN at 50 °C overnight, followed
by evaporation and washing of the residue with hexanes.
(48) Trost, B. M.; Imi, K.; Indolese, A. F. J. Am. Chem. Soc. 1993,
115, 8831.
(49) Trost, B. M.; Martinez, J. A.; Kulawiec, R. J.; Indolese, A. F.
J. Am. Chem. Soc. 1993, 115, 10402.

Article
Organometallics, Vol. 28, No. 19, 2009 5745
applications, the prolonged reaction times of curves II are
still attractive, considering the very simple catalysis setup.50
Conclusion
The air-stable and readily available complex [CpRu(η6-
naphthalene)]PF6 (2) is a highly useful precursor material for
the CpRuþ cation in complex chemistry and catalysis. It may
supplement, and in part replace, the more reactive precursors
[CpRu(MeCN)3]PF6 (1) and CpRuCl(COD) (6), which are
now commonly used for these purposes. The application
examples presented here show the utility of 2 in a range of
experiments, including the synthesis of chiral-at-metal com-
plexes and the study of their interaction with enantiopure
counterions. The synthesis of salt 4 by anion exchange in
aqueous medium is notable, because a similar reaction would
be out of reach for the moisture-sensitive precursor
[CpRu(MeCN)3]PF6 (1). The option of releasing the CpRuþ
cation in the absence of strongly coordinating solvents has
allowed us to prepare the sterically encumbered [CpRu-
(PPh3)3]þ complex cation, which is not available from
[CpRu(MeCN)3]PF6, because of the strong donor properties
of acetonitrile. The substitution reactions of 2 in acetonitrile
solution with phosphanes or other donors are very selective;
for example, the synthesis of [CpRu(dppe)(MeCN)]PF6 (7a)
by our method gives improved yields and does not suffer
from generation of bridging side-products as observed when
starting from 1 and dppe.31 The simplicity of generating sol-
vento complexes by stepwise substitution enabled us to study
the intricate complex chemistry of the CpRuþ fragment with
2-diphenylphosphinopyridine (14). Overall, the thematically
widespread application examples presented herein should
serve to promote further applications of 2 as a useful
precursor in CpRuþ complex chemistry and catalysis.
Figure 4. Kinetics of catalytic hydration of 1-octyne to octanal
(cf. Scheme 6). Yields of octanal were measured by GC with
tetradecane as internal standard. (a) Experiments with ligand
19: curve I, catalytic hydration with preformed complex
[CpRu(19)2(MeCN)]PF6; curve II, catalytic hydration with a
mixture of 2 and 19. (b) Experiments with ligand 25: curve I,
catalytic hydration with preformed complex [CpRu(25)2-
(MeCN)]PF6; curve II, catalytic hydration with a mixture of
2 and 25.
Scheme 6. Catalytic Anti-Markovnikov Hydration of 1-Octyne
the acetonitrile used for the ligand exchange inhibits the
catalytic hydration reaction, a change of solvent by evapora-
tion/redissolution of the in situ catalyst was necessary in the
earlier work. We hoped to spare this solvent change by using
acetone as solvent for both the ligand exchange and the
catalysis. 31P NMR spectroscopy of a solution of 2 and 2
Experimental Section
General Comments. All reactions were performed in degassed
˚
solvents under argon. Acetonitrile (MeCN) was stored over 3 A
molecular sieves. “Hexanes” denotes a petroleum ether fraction
(40-60 °C). [CpRu(η6-naphthalene)]PF6 (2),6 NBu3H-(()-
TRISPHAT27 (TRISPHAT is tris(tetrachlorocatecholato)-phos-
phate(V)), cinchonidinium Δ-TRISPHAT,27 diazadiene 8,33
6-(2,4,6-triphenylphenyl)-2-diphenylphosphinopyridine (2,4,6Ph3-
C6H2PyPPh2; 9),23,34 and 6-tert-butyl-2-diphenylphosphinopyri-
dine (tBuPyPPh2; 19)37,43,51 were obtained according to literature
procedures. 1,4-Diacetoxy-2-butyne (25) was prepared by acety-
lation of 2-butyne-1,4-diol (Ac2O/NEt3/DMAP; CH2Cl2). Other
materials, including (R)-(þ)-BINAP ({R}-2,20-bis-diphenylpho-
sphino-1,10-binaphthyl) and (1R,SP)-Josiphos,30 were obtained
from commercial suppliers. NMR spectra were measured at
ambient temperature (295 K), and chemical shifts δ are given in
ppm and werereferenced to internal TMS(1H) or to external TMS
via the solvent signal (13C, measured with 1H decoupling) or
externally to 85% H3PO4 (31P, measured with 1H decoupling).
Single-Crystal X-ray Diffraction. Crystal data, parameters for
intensity data collection, and convergence results are compiled
in Table 1. Data were collected with Mo KR radiation (graphite
t
equiv of BuPyPPh2 (19) in acetone-d6 showed that about
10% of the phosphane ligand 19 (δ = -4.2 ppm) had reacted
after 24 h at room temperature, generating a new species with
δ = 37.9 ppm, which is characteristic of the tris-phosphane
complex [CpRu(η1-19)3]PF6 (see above). As expected, de-
complexation of naphthalene is slow in acetone at room
temperature, but can be expected to be faster at the tempera-
ture of the actual catalysis, allowing for an in situ catalyst
generation/hydration. We thus hydrated the test substrate 1-
octyne in hot acetone with some water by adding either
(i) 5 mol % of preformed complex [CpRu(L)2(MeCN)]PF6,
or (ii) a mixture of 2 and 10 mol % of ligand 19 or 6-(2,4,6-
triisopropylphenyl)-2-diphenylphosphinopyridine (25)23,24
(Scheme 6). Figure 4 shows the corresponding reaction
progress curves of the 1-octyne hydrations. As expected
from previous work,23,43 the preformed complexes induce
a fast catalytic hydration with complete conversion within
2-3 h. However, the in situ catalysis is also success-
ful (curves II): it is characterized by an induction period
of ca. 2 h, followed by a steadily increasing catalytic con-
version that eventually reaches completion. For synthetic
˚
monochromator, λ =0.71073 A) on a Bruker D8 goniometer
with a SMART APEX CCD area detector. Absorption correc-
tion was performed by SADABS.52 Unit-cell parameters were
obtained by least-squares refinement of up to 9999 reflections.
(51) Hintermann, L.; Xiao, L.; Labonne, A. Angew. Chem. 2008, 120,
8370. Angew. Chem., Int. Ed. 2008, 47, 8246.
(52) Sheldrick, G. M. SADABS, Program for Empirical Absorption
(50) For a first application of this protocol, see: Kribber, T.;
Labonne, A.; Hintermann, L. Synthesis 2007, 2809.
€
Correction of Area Detector Data; University of Gottingen, 1996.

5746 Organometallics, Vol. 28, No. 19, 2009
Hintermann et al.
The structures were solved by direct methods (SHELXS97) and
refined by full matrix least-squares procedures based on F2 with
all measured reflections (SHELXL97).53 Non-hydrogen atoms
were refined anisotropically. Hydrogen atoms were inserted in
calculated positions and were refined using a riding model. The
absolute configuration of compound 4 was also confirmed by
evaluation of the Flack parameter.54 The crystal of 5 used for
intensity data collection proved to be a twin with respect to the
polarity of the c-axis in space group Pna21. The Flack parameter
quoted in Table 1 results from refinement as an inversion twin.
Crystallographic data for all structures have been deposited
with the Cambridge Crystallographic Data Centre as supple-
(2 mL) and overlayed with tBuOMe (3 mL) and hexanes
(10 mL). Standing overnight at 4 °C precipitated a solid, which
t
was washed with BuOMe (2 ꢀ 3 mL) and dried under high
1
vacuum. Yellow powder (241 mg, 94%). H NMR (400 MHz,
acetone-d6): 1.61 (s, 3 H, MeCN), 2.67-2.83 (m, 4 H, CH2CH2),
4.86 (s, 5 H, Cp), 7.42-7.49 (m, 8 HArl), 7.53-7.60 (m, 6 HArl),
7.89-7.94 (m, 6 HArl). 31P NMR (161 MHz, acetone-d6): -144.4
(sept, JPF = 710 Hz, PF6-), 79.3 (s). MS (ESI): m/z =
565 [CpRu(dppe)]þ. Anal. Calcd for C33H32F6NP3Ru (750.60):
C 52.81, H 4.30, N 1.87. Found: C 52.43, H 4.27, N 2.22.
[CpRu({R}-BINAP)(MeCN)]PF6 (7b). This complex was pre-
pared as described for 7a from 2 (70.6 mg, 0.161 mmol) and
(R)-(þ)-2,20-bis(diphenylphosphino)-1,10-binaphthyl (100 mg,
0.161 mmol) in MeCN (4 mL). Yellow solid: 150 mg (96%).
1H NMR (300 MHz, MeCN-d3): 2.14 (s, 3 H, noncomplexed
MeCN), 4.50 (s, 5 H, Cp), 6.30 (br d, J=8.6 Hz, 1 H), 6.65 (br d,
J = 8.7 Hz, 1 H), 6.73-6.84 (m, 2 H), 6.94-7.13 (m, 6 H),
7.19-7.27 (m, 3 H), 7.28-7.58 (m, 16 H), 7.68 (br d, J =8.2, 1
H), 7.74 (br d, J=8.2 Hz, 1 H), 7.82 (br d, J=8.9 Hz, 1 H). 1H
NMR (400 MHz, CDCl3): 1.18 (t, JPH =1.2 Hz, 3 H, MeCN),
4.48 (s, Cp, 5 H), 6.28 (d, J=8.7 Hz, 1 H), 6.62 (d, J ≈ 9 Hz, 1 H),
6.71-6.79 (m, 2 H), 6.95-7.15 (m, 6 HArl), 7.19-7.56 (m, 19 H),
7.59-7.77 (m, 3 H); selected signals for [CpRu(κ1P:κ3P,C,C-
BINAP)]PF6 (ca. 14% abundance): 4.41 (s, Cp). 31P NMR (121
MHz, MeCN-d3): -144.7 (sept, JPF=704 Hz, PF6-), 45.9 (d, JPP
= 45.8 Hz), 54.5 (d, JPP = 45.8 Hz). 31P NMR (162 MHz,
CDCl3): -144.3 (sept, JPF =713 Hz, PF6-), 47.1 (d, JPP =45.9
Hz), 55.3 (d, JPP =45.9 Hz); signals for [CpRu(κ1P:κ3P,C,C-
BINAP)]PF6: 14.6 (d, JPP =44.4 Hz), 73.8 (d, JPP =44.4 Hz).
ESI-MS: m/z=789 [CpRu(BINAP)]þ. Anal. Calcd for C51H40-
F6NP3Ru: C 62.83, H 4.14, N 1.44. Found: C 62.51, H 4.51,
N 1.17.
mentary data: CCDC 725213 (for 4 CH2Cl2) and 725214 (for 5).
3
[CpRu(η6-naphthalene)]Δ-TRISPHAT (4). Cinchonidinium
Δ-TRISPHAT (274 mg, 0.258 mmol) and 2 (109 mg, 0.248
mmol) were stirred in a mixture of CH2Cl2 (12 mL), MeOH
(5 mL), and acetone (10 mL) until the solids had completely
dissolved (ca. 30 min). Using more CH2Cl2 (ca. 8 mL), the
solution was transferred to a separatory funnel containing water
(50 mL). After thorough shaking, the organic phase was col-
lected and the water phase extracted twice with CH2Cl2 (5 mL).
The combined organic phases were filtered over a column of
neutral Al2O3 (40 ꢀ 15 mm), and the column was eluted with
more CH2Cl2 (25 mL, then 50 mL). The yellow filtrate was
evaporated to dryness to leave 288.6 mg (first fraction) and
5.6 mg (second fraction) of solids. The solids were dissolved in
CH2Cl2 (3 mL) and overlayed with tBuOMe (5 mL) and hexanes
(15 mL). After standing overnight at 4 °C, the crystalline solid
was washed with hexanes, ground, and dried under high vacuum
at 50 °C. Yield: 249 mg (94%) of solvent-free beige powder.
Mp>260 °C (dec). 1H NMR (400 MHz, acetone-d6): 5.14 (s, 5 H,
Cp), 6.46-6.50 (m, 2 H), 7.22-7.27 (m, 2 H), 7.69-7.75 (m,
2 H), 7.86-7.92 (m, 2 H). 13C NMR (100 MHz, acetone-d6): 80.4
(CH), 84.5/84.5 (Δδ = 1.2 Hz, CH), 86.5/86.5 (Δδ = 1.0 Hz,
CH), 97.9 (C), 114.2 (d, JPC = 19.9 Hz, CTRISPHAT), 122.9
(CTRISPHAT), 129.8/129.8 (Δδ = 2.9 Hz, CH), 132.1/132.1
(Δδ = 0.7 Hz, CH), 142.7 (d, JPC = 6.6 Hz, CTRISPHAT); the
splitting of signals for several enantiotopic carbons is due to the
chiral environment generated by the enantiopure counterion.
31P NMR (162 MHz, acetone-d6): -80.7 (s). ESI-MS (CHCl3):
295 [CpRu(C10H8)]þ; 768.5 TRISPHAT- (negative mode).
Anal. Calcd for C33H13Cl12O6PRu: C 37.29, H 1.23. Found:
C 37.48, H 1.53.
[CpRu({1R,SP}-Josiphos)(MeCN)]PF6 (7c). This complex
was prepared as described for 7a from 2 (73.9 mg, 0.168 mmol)
and (1R,Sp)-Josiphos (100 mg, 0.168 mmol) in MeCN (4 mL).
1
Orange foam (158 mg, 99%). H NMR (400 MHz, CDCl3),
signals for the main diastereomer (76% abundance): 0.67-2.13
(m, 21 HCy), 1.67 (dd, J=10.0, 7.5 Hz, 3 H, MeCH), 2.38-2.51
(m, 1 HCy), 2.43 (t, JPH =1.0 Hz, 3 H, MeCN), 3.51 (quint,
J=7.4 Hz, 1 H, MeCH), 3.57 (s, 5 H, Cp’Fe), 4.41-4.44 (m, 1 H,
FeC5H3), 4.47 (t, J=2.5 Hz, 1 H, FeC5H3), 4.58 (s, 5 H, CpRu),
4.61-4.64 (m, 1 H, FeC5H3), 6.76-6.86 (m, 2 HPh), 7.18-7.23
(m, 3 HPh), 7.55-7.73 (m, 3 HPh), 7.99-8.09 (m, 2 HPh); selected
signals for the minor isomer (24% abundance): 1.78 (dd, J=9.7,
7.1 Hz, 3 H, MeCH), 1.88 (t, JPH=1.0 Hz, 3 H, MeCN), 4.29 (s,
5 H, Cp’Fe), 4.75 (s, 5 H, CpRu). 31P NMR (162 MHz, CDCl3):
-144.4 (sept, JPF=713 Hz, PF6-), 38.5 (d, JPP=46.0 Hz, major
[CpRu(η2:η2-COD)(MeCN)]PF6 (5). A solution of (Z,Z)-1,5-
cyclooctadiene (0.10 mL, 0.81 mmol) and 2 (200 mg, 0.45 mmol)
in MeCN (7 mL) was stirred at room temperature for 45 h. After
evaporation, the residue was dissolved in CH2Cl2 (2 mL) and
t
overlayed with BuOMe (3 mL) and hexanes (10 mL). After
standing overnight at 4 °C, liquids were decanted, and the
diastereomer), 47.8 (d, JPP =43.8 Hz, minor), 69.3 (d, JPP
=
46.0 Hz, major), 70.3 (d, JPP =43.9 Hz, minor). ESI-MS: m/z=
761 [CpRu(Josiphos)]þ. Anal. Calcd for C43H52F6FeNP3Ru:
C 54.55, H 5.54, N 1.48. Found: C 54.91, H 5.83, N 1.34.
[CpRu{1,4-bis(2,6-diisopropylphenyl)-1,4-diaza-1,3-butadiene-
N,N0}(MeCN)]PF6 (8). A solution of 2 (150 mg, 0.341 mmol)
and 1,4-bis(2,6-diisopropyl)phenyl-1,4-diaza-1,3-butadiene
(135 mg, 0.358 mmol) in MeCN (4 mL) was stirred at room
temperature for 24 h. The residue of evaporation was dissolved
t
precipitate was washed with BuOMe (2 ꢀ 3 mL) and dried
under high vacuum: yellow solid (196 mg, 94%). Crystals for the
X-ray structure analysis were obtained by diffusion of hexanes
into an acetone solution of the complex. H NMR (400 MHz,
1
acetone-d6): 2.13-2.23 (m, 4 H, CH2), 2.24-2.35 (m, 2 H, CH2),
2.40-2.51 (m, 2 H, CH2), 2.71 (s, 3 H, MeCN), 4.36-4.46 (m,
2 H, CdCH), 5.32 (s, 5 H, Cp), 5.66-5.75 (m, 2 H, CdCH).
13C NMR (100 MHz, acetone-d6): 4.4 (CH3), 28.0 (CH2), 32.4
(CH2), 85.3 (Cp), 85.4 (CH), 86.8 (CH), 130.5 (MeCN); the weak
signal of MeCN is insecure. 13P NMR (162 MHz, acetone-d6):
-144.4 (sept, JPF=710 Hz, PF6-). ESI-MS: m/z=734.5 [2 M -
MeCN - PF6]þ, 274 [CpRu(COD)]þ. IR (KBr, cm-1): 2846 (m),
2282 (w), 841 (s). Anal. Calcd for C15H20F6NPRu: C 39.13,
H 4.38, N 3.04. Found: C 39.56, H 4.34, N 2.87.
t
in CH2Cl2 (2 mL) and overlayed with BuOMe (3 mL) and
hexanes (10 mL). After standing overnight at 4 °C, liquids were
decanted and the residual solid was washed with tBuOMe (2 ꢀ
3 mL) and dried under high vacuum. Brown-violet powder,
239 mg (96%). 1H NMR (400 MHz, CDCl3): 1.16 (d, J=6.8 Hz,
6 H, 2 ꢀ Me), 1.23 (d, J=6.8 Hz, 12 H, 4 ꢀ Me), 1.23 (d, J=6.8
Hz, 6 H, 2 ꢀ Me), 2.52 (s, 3 H, MeCN), 2.57 (sept, J =6.8 Hz,
2 H, CHMe2), 3.06 (sept, J=6.8 Hz, 2 H, 2 ꢀ CHMe2), 4.28 (s,
5 H, Cp), 7.19 (dd, J=7.5, 1.5 Hz, 2 HArl), 7.28 (dd, J=7.8, 1.5
Hz, 2 HArl), 7.34 (t, J =7.7 Hz, 2 HArl), 8.52 (s, 2 H, NdCH).
13C NMR (100 MHz, CDCl3): 4.1 (CH3), 22.8 (CH3),
24.2 (CH3), 24.5 (CH3), 26.7 (CH3), 27.7 (CH), 28.1 (CH),
79.8 (CH), 123.2 (CH), 124.5 (CH), 127.9 (CH), 130.5 (C,
MeCN), 138.2 (C), 139.2 (C), 150.0 (C), 166.0 (CH). 31P NMR
[CpRu(dppe)(MeCN)]PF6 (7a). A solution of 2 (150 mg,
0.34 mmol) and 1,2-bis(diphenylphosphino)ethane (144 mg,
0.36 mmol) in MeCN (4 mL) was stirred at room temperature
for 24 h. After evaporation, the residue was dissolved in CH2Cl2
(53) Sheldrick, G. M. Acta Crystallogr., Sect. A 2008, 64, 112.
(54) Flack, H. D. Acta Crystallogr., Sect. A 1983, 39, 876.

Article
Organometallics, Vol. 28, No. 19, 2009 5747
(162 MHz, CDCl3): -144.7 (sept, JPF=713 Hz, PF6-). ESI-MS:
m/z = 543 [CpRu(diazadiene)]þ. Anal. Calcd for C33H44-
F6N3PRu þ 0.5 H2O: C 53.72, H 6.15, N 5.70. Found: C
53.58, H 5.99, N 5.53.
1H NMR (400 MHz, acetone-d6), signals for 16: 2.22 (d, J =
1.9 Hz, 3 H, MeCN), 4.68 (s, 5 H, Cp), 7.51-7.75 (m, 10 H),
7.83-7.90 (m, 2 H), 8.08 (tt, J=7.9, 1.5 Hz, 1 HPy), 8.90 (d ꢀ m,
J=5.3 Hz, 1 HPy). 1H NMR (300 MHz, MeCN-d3), signals for
15: 1.97 (s, 3 H, free MeCN), 4.46 (s, 5 H, Cp), 7.32 (ddt, J=7.8,
4.5, 1.1 Hz, 1 HPy), 7.38 (dddd, J=7.7, 4.7, 2.5, 1.2 Hz, 1 HPy),
7.43-7.55 (m, 10 HPh), 7.76 (tdd, J =7.8, 3.4, 1.8 Hz, 1 HPy),
8.73 (dddd, J=4.7, 1.8, 1.0, 0.7 Hz, 1 HPy). 31P NMR (162 MHz,
acetone-d6), signals for 16: -144.4 (sept, JPF =708 Hz, PF6-),
-0.5 (s). 31P NMR (121 MHz, MeCN-d3), signals for 15: -144.7
(sept, JPF =708 Hz, PF6-), 50.4 (s). ESI-MS: m/z =430 [Cp-
Ru(14)]þ. Anal. Calcd for 16, C24H22F6N2P2Ru: C 46.84,
H 3.60, N 4.55. Found: C 46.91, H 3.99, N 4.19.
[CpRu(2,4,6Ph3C6H2PyPPh2-KP)(MeCN)2]PF6 (10) and [CpRu-
(
2,4,6Ph3C6H2PyPPh2-κP,κN)(MeCN)]PF6 (11). Pyridylphos-
phane 9 (646 mg, 1.138 mmol) was suspended in a solution of
2 (500 mg, 1.138 mmol) in MeCN (20 mL) and stirred at room
temperature for 20 h. The resulting yellow solution was eva-
porated and the residue washed with hexanes. Bright yellow
powder: 1.09 g (quant). The solid has a variable composi-
tion, losing coordinated MeCN with formation of 11. 1H NMR
(400 MHz, acetone-d6), data for 10 (65% abundance): 2.05 (s,
free MeCN), 2.23 (d, JPH=1.4 Hz, 6 H, 2 ꢀ MeCN), 4.43 (s, 5 H,
Cp), 7.15-7.99 (m, 27 HArl), 7.70 (s, 2 HArl), 7.97 (t, J=1.8 Hz, 1
[CpRu(PyPPh2-KP,KN)(PyPPh2-KP)]PF6 (18). A solution
of 2 (70 mg, 0.16 mmol) and 14 (83.9 mg, 0.32 mmol) in MeCN
(4 mL) was stirred at 50 °C for 21 h. The reaction mixture was
evaporated, the residue dissolved in CH2Cl2 (2 mL), and the
solution overlayed with tBuOMe (3 mL) and hexanes (10 mL).
After standing at 4 °C overnight, liquids were decanted and the
solid was washed with hexanes. Drying under vacuum gave 18 as
H
Arl); data for 11 (35% abundance): 1.66 (d, JPH =2.0, 3 H,
MeCN), 4.32 (s, 5 H, Cp), 7.09-7.99 (m, 30 HArl). 31P NMR
(162 MHz, acetone-d6): -144.4 (sept, JPF =709 Hz, PF6-), 0.1
(s, 11), 51.1 (s, 10). ESI-MS: m/z =734.3 [CpRu(9)]þ.
[CpRu(Ph3C6H2PyPPh2-KP)2(MeCN)]PF6 (12). A mixture of
9 (1.14 g, 2.0 mmol) and 2 (440 mg, 1.0 mmol) in MeCN (25 mL)
was stirred for 10 h at 60-65 °C. The suspension turned into a
yellow solution. After evaporation and drying under high
vacuum, hexanes (10 mL) were added to the yellow resinous
residue and the mixture was kept at 45 °C for 1 h. The solid was
ground to a powder by means of a spatula and the suspension
filtered. The solid was washed with hexanes (2 ꢀ 10 mL) and
1
a yellow foam (131 mg, 98%). H NMR (400 MHz, CDCl3):
4.46 (s, 5 H, Cp), 6.70 (dd, J=7.8, 2.8 Hz, 1 HPy), 6.95-7.00 (m,
1 HPy), 7.06-7.48 (m, 23 HArl), 7.76 (tt, J=7.8, 1.4 Hz, 1 HPy),
8.07 (br d, J = 4.1 Hz, 1 HPy), 8.52 (d, J = 5.3 Hz, 1 HPy).
31P NMR (161 MHz, CDCl3): -144.3 (sept, JPF = 713 Hz,
PF6-), -8.2 (d, JPP=38.2 Hz), 51.2 (d, JPP=38.2 Hz). ESI-MS:
m/z = 692 [CpRu(14)2]þ, 430 [CpRu(14)]þ. Anal. Calcd for
C39H33F6N2P3Ru: C 55.92, H 3.97, N 3.34. Found: C 56.26,
H 4.35, N 3.00.
In Situ Ligand Exchange Experiments of 1 or 2 with 2-
Diphenylphosphinopyridine (14): 15, 16, [CpRu(PyPPh2-κP)2-
(MeCN)]PF6 (17), and 18. (a) Reaction of 2 with 14 (1:1 ratio)
in MeCN-d3: In an NMR tube, 2 (10 mg, 0.023 mmol) and 14
(6.0 mg, 0.023 mmol) were dissolved in degassed MeCN-d3
(0.7 mL) and kept at room temperature for 20 h. (b) Reaction
of 2 with 14 (1:2 ratio) in MeCN-d3: In an NMR tube, 2 (10 mg,
0.023 mmol) and 14 (12.0 mg, 0.046 mmol) were dissolved in
degassed MeCN-d3 (0.7 mL) and placed in an oil bath at 50 °C
for 20 h. (c) Reaction of CpRu(MeCN)3]PF6 (1) with 14 (1:2
ratio) in CDCl3: A mixture of 1 (10 mg, 0.023 mmol) and 14 (11.9
mg, 0.045 mmol) in degassed CDCl3 (0.6 mL) was kept at room
temperature for 24 h. See Table 2 and text for results.
1
dried under high vacuum. Yellow powder: 1.29 g (99%). H
NMR (400 MHz, CDCl3): 2.01 (br t, JPH ≈ 1.2 Hz, 3 H, MeCN),
4.00 (s, 5 H, Cp), 6.73-6.79 (m, 3 HArl), 6.82-6.95 (m, 9 HArl),
6.97-7.13 (m, 23 HArl), 7.16-7.22 (m, 3 HArl), 7.25-7.34 (m,
4 HArl), 7.36-7.42 (m, 2 HArl), 7.44-7.50 (m, 6 HArl), 7.66 (s,
4 HArl), 7.68-7.73 (m, 4 HArl), 7.82-7.87 (m, 2 HArl). 31P NMR
(162 MHz, CDCl3): -144.4 (sept, JPF=713 Hz, PF6-), 44.1 (s).
31P NMR (121 MHz, MeCN-d3): -144.6 (sept, JPF =706 Hz,
PF6-), 43.2 (s). ESI-MS: m/z = 1301 [CpRu(9)2]þ, 734 [Cp-
Ru(9)]þ. Anal. Calcd for C89H68F6N3P3Ru: C 71.86, H 4.61,
N 2.82. Found: C 72.02, H 4.84, N 2.71.
[CpRu(2,4,6Ph3C6H2PyPPh2-KP)2(MeCN)](()-TRISPHAT
(13). Tributylammonium (()-TRISPHAT27 (290 mg, 0.303
mmol) and 12 (444 mg, 0.2985 mmol) were stirred in CH2Cl2
(10 mL) for 30 min to give a clear yellow solution. After
evaporation to 2-3 mL, the solution was placed on top of a
chromatography column (SiO2, wetted with CH2Cl2/hexanes,
1:1) and eluted with CH2Cl2/hexanes 60:40 f 70:30 f 100:0.
The yellow, pure product fractions (TLC-control) were com-
bined and evaporated. The solid residue was washed with
hexanes and dried under vacuum. Bright yellow foam: 670 mg
(90%), as clathrate with cyclohexane (derived from the “hex-
anes” fraction). 1H NMR (400 MHz, C6D6): 1.40 (s, cy-
clohexane), 1.74 (br t, J ≈ 1.3 Hz, 3 H, MeCN), 3.97 (s, 5 H,
Cp), 6.61 (br d, J=7.6, 2 H), 6.72-6.83 (m, 8 H), 6.92-7.13 (m,
34 H), 7.17-7.21 (m, 2 H), 7.24-7.29 (m, 5 H), 7.50-7.55 (m,
4 H), 7.61-7.66 (m, 1 H), 7.72 (q, J ≈ 1.2 Hz, 4 H). 31P NMR
(161 MHz, C6D6): -79.9 (s, TRISPHAT), 44.2 (s). ESI-MS:
m/z = 1301 [CpRu(9)2]þ, 734 [CpRu(9)]þ. Anal. Calcd for
C107H68Cl12N3O6P3Ru þ 1.5C6H12: C 62.27, H 3.87, N 1.88.
Found: C 62.33, H 3.73, N 1.85.
[CpRu(PyPPh2-KP)(MeCN)2]PF6 (15) and [CpRu(PyPPh2-
κP,κN)(MeCN)]PF6 (16). A solution of 2 (66 mg, 0.15 mmol)
and 2-diphenylphosphinopyridine (14; 39.9 mg, 0.15 mmol) in
MeCN (3 mL) was stirred at room temperature for 20 h. The
solution was evaporated under vacuum (10 mbar), and the
residue was dissolved in CH2Cl2 (2 mL) and overlayed with
tBuOMe (3 mL) and hexanes (10 mL). After standing at 4 °C
overnight, filtration, washing with hexanes, and drying under
vacuum gave 16 (90 mg, 97%) as a yellow foam. The NMR
spectrum of 16 is observed in acetone-d6 or CDCl3 solution
(>95% abundance), whereas the spectrum for 15 (>95%
abundance) is observed when 16 is dissolved in MeCN-d3.
[CpRu(2,4,6Ph3C6H2PyPPh2-KP)(tBuPyPPh2-KP)(MeCN)-
]PF6 (20). A suspension of 2 (100 mg, 0.228 mmol) and 9 (129
mg, 0.227 mmol) in MeCN (8 mL) was stirred at room tem-
perature for 20 h. After evaporation under vacuum, the residue
was dissolved in acetone (5 mL), 9 (72.7 mg, 0.228 mmol) was
added at 0 °C, and the solution was stirred at room temperature
for 3 h. After evaporation, the residue was dissolved in CH2Cl2
(2 mL) and overlayed with tBuOMe (3 mL) and hexanes
(10 mL). After standing overnight at 4 °C, liquids were decanted
t
and the solid was washed with BuOMe (2 ꢀ 3 mL). Drying
under high vacuum gave a bright yellow powder: 262 mg (93%).
t
1H NMR (300 MHz, CDCl3): 1.33 (s, 9 H, Bu), 2.12 (t, J =
1.2 Hz, 3 H, MeCN), 4.14 (s, 5 H, Cp), 6.57 (dd, J=7.6, 3.5 Hz,
1 H), 6.73-6.82 (m, 2 H), 6.90-7.54 (m, 33 H), 7.68-7.78
(m, 4 H), 7.82-7.88 (m, 3 H). 31P NMR (121 MHz, CDCl3):
-144.3 (sept, JPF = 709 Hz, PF6-), 42.6 (d, JPP = 34.9 Hz),
44.4 (d, JPP =34.9 Hz). ESI-MS: m/z =1053 [CpRu(9)(19)]þ,
734 [CpRu(9)]þ, 486 [CpRu(19)]þ. Anal. Calcd for C69H60-
F6N3P3Ru þ 0.5H2O: C 66.39, H 4.93, N 3.37. Found: C
66.62, H 5.45, N 3.04.
[CpRu(2,4,6Ph3C6H2PyPPh2-KP)(tBuPyPPh2-KP)(MeCN)]-
Δ-TRISPHAT (21). A solution of 4 (47 mg, 0.044 mmol) and
9 (24.9 mg, 0.044 mmol) in MeCN (3 mL) was stirred for
20 h at room temperature, followed by evaporation of the
solvent under vacuum. To the residue were added 19 (14.0 mg,
0.044 mmol) and acetone (2 mL), and the solution was stirred at
room temperature for 2 h. The solvent was evaporated and the
residue dissolved in CH2Cl2 (0.5 mL). After overlaying with

5748 Organometallics, Vol. 28, No. 19, 2009
Hintermann et al.
hexanes (5 mL) and standing overnight at 4 °C, liquids were
decanted and the solid was washed with hexanes (2 ꢀ 3 mL).
Drying under high vacuum gave a bright yellow powder (76 mg,
Catalytic Reactions: 7,8-Diacetoxymethyltricyclo[4.2.2.02,5]-
dec-7-ene (26).48 The catalyst 5 (11.5 mg, 0.025 mmol, 5 mol %;
or 4.6 mg, 0.01 mmol, 2 mol %) or 2 (11.0 mg, 0.025 mmol,
5 mol %) was added to a solution of (Z,Z)-1,5-cyclooctadiene
(65 mg, 74 μL, 0.6 mmol) and 1,4-diacetoxy-2-butyne (85 mg,
0.50 mmol) in degassed methanol (5 mL) under argon. The
reaction mixture was stirred at the indicated temperature
(Table 4) until TLC indicated completion of the reaction. The
solvent was removed under vacuum, and the residue purified by
chromatography (SiO2, tBuOMe/hexanes, 1:10) to give a color-
less liquid that solidified on standing. See Table 4 for results.
Mp: 53.5-55 °C. 1H NMR (400 MHz, CDCl3): 1.11-1.21 (m,
2 H), 1.85-1.95 (m, 2 H), 1.97-2.02 (m, 2 H), 2.05 (s, 6 H, 2 ꢀ
MeCO2), 2.09-2.21 (m, 4 H), 2.48-2.51 (m, 2 H), 4.73 (AB
system, J ≈ 13 Hz, 4 H, 2 ꢀ CH2OAc). 13C NMR (100 MHz,
CDCl3): 18.0 (CH2), 20.4 (CH2), 21.1 (CH3), 35.1 (CH), 36.6
(CH), 61.6 (CH2), 138.3 (CH), 170.8 (C). EI-MS: m/z (%)=278
(1) Mþ, 218 (28), 176 (100). IR (KBr, cm-1): 2943, 1732 (CdO),
1240. Anal. Calcd for C16H22O4: C 69.04, H 7.97. Found:
C 68.91, H 7.85.
92%). 1H NMR (300 MHz, CDCl3), two shifts given in case of
t
diastereomeric signals: 1.35 (s, 9 H, Bu), 1.95/1.96 (t, JPH
=
1.4 Hz, 3 H, MeCN), 4.02/4.03 (s, 5 H, Cp), 6.42-6.49 (m, 1 H),
6.61-6.69 (m, 1 H), 6.74-6.84 (m, 2 H), 6.90-7.55 (m, 33 H),
7.71-7.79 (m, 4 H), 7.81-7.88 (m, 2 H). 31P NMR (121 MHz,
CDCl3): -81.1 (s, TRISPHAT), 41.9 (d, JPP=34.2 Hz), 42.0 (d,
J
PP =34.2 Hz), 43.8 (d, JPP =33.5 Hz), 44.1 (d, JPP =33.5 Hz).
ESI-MS: m/z = 1053 [CpRu(9)(19)]þ, 734 [CpRu(9)þ], 486
[CpRu(19)]þ; negative mode: 769 TRISPHAT-. Anal. Calcd
for C87H60Cl12N3O6P3Ru: C 56.09, H 3.25, N 2.26. Found:
C 56.20, H 3.52, N 1.98.
[CpRu(tBuPyPPh2-KP)3]PF6 (23). A mixture of 2 (45.0 mg,
0.102 mmol) and 19 (130 mg, 0.41 mmol) in acetone (5 mL) and
water (2 drops) was heated to 90 °C in a closed vessel for 35 h.
The yellow solution was evaporated to a small volume and
overlayed with hexanes (5 mL). After standing overnight at 4 °C,
the solid was washed with tBuOMe and hexanes and dried under
high vacuum. Crystalline yellow powder, 91 mg (70%). 1H
7-Hydroxy-5-dodecen-2-one.49 A solution of 3-buten-2-ol
(28; 90 μL, 1.0 mmol), 1-octyn-3-ol (27; 75 μL, 0.50 mmol),
and 5 (11.5 mg, 0.025 mmol, 5 mol %) in DMF/H2O (1:1, 3 mL)
was stirred at the specified temperature until completion of the
reaction, as judged by TLC. After dilution with water and
t
NMR (300 MHz, CDCl3): 1.31 (s, 27 H, Bu), 5.08 (s, 5 H,
Cp), 6.45 (d, J =6.7 Hz, 3 H), 6.90-7.07 (m, 23 H), 7.24-7.45
=
(m, 13 H). 31P NMR (121 MHz, CDCl3): -144.3 (sept, JPF
713, PF6-), 38.4 (s). ESI-MS: m/z=805 [CpRu(19)2]þ, 486 [Cp-
Ru(19)]þ. Anal. Calcd for C68H71N3F6P4Ru 2H2O: C 62.57,
extraction with BuOMe, the organic phase was evaporated
t
3
H 5.79, N 3.22. Found: C 62.37, H 5.53, N 3.00.
and the residue purified by column chromatography (SiO2,
tBuOMe/hexanes, 1:3-1:1) to give a yellowish liquid. See
Table 5 for results. Known compound.49 1H NMR (400 MHz,
CDCl3): 0.88 (t, J =7.1 Hz, 3 H, Me), 1.21-1.58 (m, 8 H, 4 ꢀ
CH2), 1.83 (br s, 1 H, OH), 2.14 (s, 3 H, Me), 2.31 (q, J=7.2 Hz,
2 H, CH2), 2.53 (t, J =7.4 Hz, 2 H, CH2), 4.02 (q, J =6.7 Hz,
1 H), 5.49 (ddt, J =15.4, 6.8, 1.3 Hz, 1 HCdC), 5.62 (dtd, J =
15.4, 6.4, 0.8 Hz, 1 HCdC). 13C NMR (100 MHz, CDCl3): 14.0
(CH3), 22.6 (CH2), 25.1 (CH2), 26.2 (CH2), 29.9 (CH3) 31.7
(CH2), 37.2 (CH2), 43.0 (CH2), 72.7 (CH), 129.4 (CH), 134.0
(CH), 207.8 (CdO).
Catalytic Anti-Markovnikov Hydration of 1-Octyne. (a) Pre-
paration of catalyst complexes: A Schlenk flask was charged
with 2 (22 mg, 0.05 mmol), ligand 19 or 25 (32 mg or 47 mg,
0.10 mmol), and MeCN (degassed, 3 mL). The mixture was
stirred at 60 °C for 6 h or preferably overnight. The solvent was
removed in vacuo to give a yellow powder or resin, which was
used as the catalyst. (b) Catalytic reaction for kinetic measure-
ments: A solution of 1-octyne (150 μL, 1 mmol, 1 equiv), H2O
(5 mmol, 5 equiv), and tetradecane (100 μL) in acetone (4 mL)
was added either to the Schlenk flask containing the in situ
catalyst (see above) or to a Schlenk flask containing a mixture of
2 (22mg, 0.05 mmol)andligand19 or 25 (32or 47mg, 0.10 mmol).
The solution was stirred at 60 °C. Aliquots were removed at
regular intervals to monitor reaction progress by GC analysis
with FID detection. Quantification was based on independently
determined response factors of the tetradecane standard relative
to 1-octyne and octanal. The results are displayed in Figure 4.
[CpRu(PPh3)3](Δ)-TRISPHAT (24).55 A solution of 4 (70.2
mg, 0.066 mmol) and PPh3 (74.2 mg, 0.28 mmol) in acetone
(3 mL) was stirred at 90 °C for 32 h. The solvent was evaporated
under vacuum, and the residue was dissolved in CH2Cl2 (1 mL)
and overlayed with tBuOMe (2 mL) and hexanes (5 mL). After
standing overnight at 4 °C, liquids were decanted and the
t
precipitate was washed with BuOMe (2 ꢀ 3 mL) and dried
under high vacuum to give a yellow solid (108 mg, 95%). The
product is light sensitive and unstable in acetone-d6 (partial
dissociation) or CDCl3 (oxidation). 1H NMR (400 MHz,
CD2Cl2): 4.49 (s, 5 H, Cp), 6.88-6.96 (m, 18 HPh) 7.09-7.18
(m, 18 HPh), 7.34-7.40 (m, 9 HPh). 13P NMR (121 MHz,
CD2Cl2): -81.2 (s, TRISPHAT-), 32.3 (s). ESI-MS: m/z =
691 [CpRu(PPh3)2]þ, 429 [CpRu(PPh3)]þ. Anal. Calcd for
C77H50Cl12O6P4Ru H2O: C 53.16, H 3.01. Found: C 53.32, H
3
3.27.
[CpRu(PPh3)3]PF6. A solution of 2 (45 mg, 0.10 mmol) and
PPh3 (111 mg, 0.42 mmol) in acetone (3 mL) was heated to 90 °C
in a pressure tube for 30 h. The dark yellow solution was
evaporated to a small volume, overlayed with tBuOMe
(6 mL), and kept at 4 °C overnight. After decantation, the
residue was dissolved in CH2Cl2 (1 mL) and overlayed with
hexanes (6 mL). After standing overnight at 4 °C, liquids were
decanted and the semisolid was washed with hexanes and dried
under high vacuum. Yellow resin, 70 mg (71%). No correspond-
ing analysis was obtained. The compound easily dissociates PPh3
to give solvated [CpRu(PPh3)2(S)]þ complexes, where S is either a
coordinating solvent or water. In CDCl3, slow decomposition
with partial generation of CpRu(PPh3)2Cl, δ(31P) = 38.8 ppm,
is observed. 1H NMR (300 MHz, acetone-d6), signals for
[CpRu(PPh3)3]þ (60% abundance): 4.61 (s, 5 H, Cp), 7.02-7.54
(m, 45 H, Ph); selected signals for [CpRu(PPh3)2(S)]þ (40%
abundance): 4.75 (s, 5 H, Cp). 31P NMR (121 MHz, acetone-
d6):-144.3(sept, JPF=709 Hz, PF6-), -5.7 (s, PPh3), 32.6(s, [Cp-
Ru(PPh3)3]þ), 40.5 (s, [CpRu(PPh3)2(S)]þ).
Acknowledgment. This work was supported by the
Deutsche Forschungsgemeinschaft (Emmy Noether
Programm) and the Fonds der Chemischen Industrie.
We thank Prof. Carsten Bolm, RWTH Aachen Univer-
sity, for continued support, and Jonathan J. Jodry for
a copy of his doctoral thesis.
Supporting Information Available: Crystallographic data for
4 CH2Cl2 and 5 as CIF data files. This material is available free
of charge via the Internet at http://pubs.acs.org.
(55) A referee suspects that racemization of the Δ-TRISPHAT
counterion may have occurred under the conditions of this ligand
exchange reaction; this cannot currently be excluded.
3