C-N and C-C coupling reactions: Preparation of new N-heterocyclic ruthenium derivatives

Article abstract of DOI:10.1021/om020652r

Three novel types of complexes containing heterocyclic ligands are prepared by condensation of the allenylidene ligand of [Ru(η⁵-C₅H₅)(=C=C=CPh₂)(CO) (PⁱPr₃)]BF₄ (1) with propargylamines. Complex 1 reacts with propargylamine to give initially [Ru(η⁵-C₅H₅)- {C(CH=CPh₂)=NHCH₂C≡CH}(CO)(Pⁱ Pr₃)]BF₄ (2). Treatment of 2 with KOH in methanol affords the bicyclic derivative Ru(η⁵-C₅H₅){4-methylidene-6,6-diphenyl-2-az abicyclo[3.1.0]- hex-2-en-1-yl}(CO)(PⁱPr₃) (3). The formation of 3 takes place via the intermediate Ru(η⁵- C₅H₅){C(CH=CPh₂)=NCH₂C≡CH}(CO) (PⁱPr₃) (4), which is isolated when the deprotonation of 2 is carried out in tetrahydrofuran as solvent. In contrast to propargylamine, the addition of 1,1-diethylpropargylamine to 1 leads to the dihydropyridiniumyl derivative [Ru(η⁵-C₅H₅)-2,2-diethyl-5- diphenylidene-2,5-dihydropyridinium-6-yl(CO)(PⁱPr₃)] BF₄ (5) in a one-pot synthesis. Complex 1 also reacts with N-methylpropargylamine. The reaction affords [Ru-(η⁵-C₅H₅) {C(CH=CPh₂)=N(CH₃)CH₂C≡CH}(CO) (PⁱPr₃)]BF₄ (6). Treatment of 6 with sodium methoxide, at -78°C, gives a 1:1 mixture of the dihydronaphthopyrrolyl diastereomers (R_RuS_C,S_RuR_C)- Ru(η⁵-C₅H₅){9-phenyl-4, 4a-dihydronaphtho[2,3-c]-1-pyrrolyl}(CO)(PⁱPr₃) (7a) and (R_RuR_C,S_RuS_C)-Ru(η⁵- C₅H₅){9-phenyl-4,4a-dihydronaphtho[2,3-c]- 1-pyrrolyl}(CO)(PⁱPr₃) (7b). Complexes 3 and 5 and the enantiomeric mixture 7a have been characterized by X-ray diffraction analysis.

Full text of DOI:10.1021/om020652r

162
Organometallics 2003, 22, 162-171
C-N a n d C-C Cou p lin g Rea ction s: P r ep a r a tion of New
N-Heter ocyclic Ru th en iu m Der iva tives
Mar´ıa L. Buil,* Miguel A. Esteruelas,*,† Ana M. Lo´pez, and Enrique On˜ate
Departamento de Quı´mica Inorga´nica-Instituto de Ciencia de Materiales de Arago´n,
Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain
Received August 12, 2002
Three novel types of complexes containing heterocyclic ligands are prepared by condensa-
tion of the allenylidene ligand of [Ru(η5-C5H5)(dCdCdCPh2)(CO)(PiPr3)]BF4 (1) with
propargylamines. Complex 1 reacts with propargylamine to give initially [Ru(η5-C5H5)-
{C(CHdCPh2)dNHCH2CtCH}(CO)(PiPr3)]BF4 (2). Treatment of 2 with KOH in methanol
affords the bicyclic derivative Ru(η5-C5H5){4-methylidene-6,6-diphenyl-2-azabicyclo[3.1.0]-
hex-2-en-1-yl}(CO)(PiPr3) (3). The formation of 3 takes place via the intermediate Ru(η5-
C5H5){C(CHdCPh2)dNCH2CtCH}(CO)(PiPr3) (4), which is isolated when the deprotonation
of 2 is carried out in tetrahydrofuran as solvent. In contrast to propargylamine, the addition
of 1,1-diethylpropargylamine to 1 leads to the dihydropyridiniumyl derivative [Ru(η5-C5H5)-
{2,2-diethyl-5-diphenylidene-2,5-dihydropyridinium-6-yl)(CO)(PiPr3)]BF4 (5) in a one-pot
synthesis. Complex 1 also reacts with N-methylpropargylamine. The reaction affords [Ru-
(η5-C5H5){C(CHdCPh2)dN(CH3)CH2CtCH}(CO)(PiPr3)]BF4 (6). Treatment of 6 with sodium
methoxide, at -78 °C, gives a 1:1 mixture of the dihydronaphthopyrrolyl diastereomers
(RRuSC,SRuRC)-[Ru(η5-C5H5){9-phenyl-4,4a-dihydronaphtho[2,3-c]-1-pyrrolyl})(CO)(PiPr3) (7a )
and (RRuRC,SRuSC)-[Ru(η5-C5H5){9-phenyl-4,4a-dihydronaphtho[2,3-c]-1-pyrrolyl})(CO)(PiPr3)
(7b). Complexes 3 and 5 and the enantiomeric mixture 7a have been characterized by X-ray
diffraction analysis.
In tr od u ction
etc), which require multistep procedures in conventional
organic synthesis.
Today it is rare to find a complete total synthesis that
does not use a transition-metal-based reaction. In this
respect, carbene complexes are one of the most useful
tools.1
The coordination of the π-acidic carbonyl group to the
metallic fragment containing the allenylidene ligand
enhances the reactivity associated with the allenylidene
spine.8 Thus, as a part of our work in the chemistry of
allenylidene complexes ofplatinum-group metals,4-7,8a,b,d,9
we have recently reported that the CR-Câ double bond
of the diphenylallenylidene ligand of the complex [Ru-
(η5-C5H5)(dCdCdCPh2)(CO)(PiPr3)]BF4 adds the N-H
The chemistry of allenylidene compounds LnMdCd
CdCR2, which belong to the series of unsaturated
carbene derivatives LnMdC(dC)ndCR2 (n > 0), has been
much less studied than that of the carbene complexes.
However, recent research indicates that their potential
can become greater.2 The preparation of transition-
metal allenylidenes is very easy,3 and the presence of
three reactive centers (unsaturated C3 chain) or more
(unsaturated chain plus substituents) in the η1-carbon
ligand allows one to build, in one or two steps, organic
skeletons (naphthofuranyl,4 pyrazolopyrazolyl,5 azeti-
dine, hexahydroquinoline,6 pyridopyridinyl, thiazinyl,7
(4) (a) Esteruelas, M. A.; Go´mez, A. V.; Lo´pez, A. M.; On˜ate, E.; Ruiz,
N. Organometallics 1998, 17, 2297. (b) Esteruelas, M. A.; Go´mez, A.
V.; Lo´pez, A. M.; Oliva´n, M.; On˜ate, E.; Ruiz, N. Organometallics 2000,
19, 4.
(5) Esteruelas, M. A.; Go´mez, A. V.; Lo´pez, A. M.; On˜ate, E.; Ruiz,
N. Organometallics 1998, 17, 3567.
(6) Esteruelas, M. A.; Go´mez, A. V.; Lo´pez, A. M.; On˜ate, E.; Ruiz,
N. Organometallics 1999, 18, 1606.
(7) Bernad, D. J .; Esteruelas, M. A.; Lo´pez, A. M.; Oliva´n, M.; On˜ate,
E.; Puerta, M. C.; Valerga, P. Organometallics 2000, 19, 4327.
(8) (a) Esteruelas, M. A.; Go´mez, A. V.; Lahoz, F. J .; Lo´pez, A. M.;
On˜ate, E.; Oro, L. A. Organometallics 1996, 15, 3423. (b) Esteruelas,
M. A.; Go´mez, A. G.; Lo´pez, A. M.; Modrego, J .; On˜ate, E. Organome-
tallics 1997, 16, 5826. (c) Gamasa, M. P.; Gimeno, J .; Gonza´lez-
Bernardo, C.; Borge, J .; Garc´ıa-Granda, S. Organometallics 1997, 16,
2483. (d) Esteruelas, M. A.; Go´mez, A. V.; Lo´pez, A. M.; Puerta, M. C.;
Valerga, P. Organometallics 1998, 17, 4959. (e) Esteruelas, M. A.;
Go´mez, A. V.; Lo´pez, A. M.; Modrego, J .; On˜ate, E. Organometallics
1998, 17, 5434. (f) Baya, M.; Buil, M. L.; Esteruelas, M. A.; Lo´pez, A.
M.; On˜ate, E.; Rodr´ıguez, J . R. Organometallics 2002, 21, 1841.
(9) (a) Edwards, A. J .; Esteruelas, M. A.; Lahoz, F. J .; Modrego, J .;
Oro, L. A.; Schrickel, J . Organometallics 1996, 15, 3556. (b) Esteruelas,
M. A.; Oro, L. A.; Schrickel, J . Organometallics 1997, 16, 796. (c)
Bohanna, C.; Callejas, B.; Edwards, A. J .; Esteruelas, M. A.; Lahoz,
F. J .; Oro, L. A.; Ruiz, N.; Valero, C. Organometallics 1998, 17, 373.
(d) Crochet, P.; Esteruelas, M. A.; Lo´pez, A. M.; Ruiz, N.; Tolosa, J . I.
Organometallics 1998, 17, 3479. (e) Baya, M.; Crochet, P.; Esteruelas,
M. A.; Gutie´rrez-Puebla, E.; Lo´pez, A. M.; Modrego, J .; On˜ate, E.; Vela,
N. Organometallics 2000, 19, 2585.
* To whom correspondence should be addressed.
† E-mail: maester@posta.unizar.es. Fax: 34 976761187.
(1) For example: (a) Harvey, D. F.; Sigano, D. M. Chem. Rev. 1996,
96, 271. (b) Schuster, M.; Blechert, S. Angew. Chem., Int. Ed. Engl.
1997, 36, 2036. (c) Dias, E. L.; Nguyen, S. T.; Grubbs, R. H. J . Am.
Chem. Soc. 1997, 119, 3887. (d) Barluenga, J .; Aznar, F.; Ferna´ndez,
M. Chem. Eur. J . 1997, 3, 1629. (e) Fu¨rstner, A. Angew. Chem., Int.
Ed. 2000, 39, 3012. (f) de Mejiere, A.; Schirmer, H.; Duetsch, M. Angew.
Chem., Int. Ed. 2000, 39, 3964. (g) Aumann, R., Eur. J . Org. Chem.
2000, 17. (h) Trnka, T. M.; Grubbs, R. H. Acc. Chem. Res. 2001, 34,
18.
(2) (a) Werner, H. Chem. Commun. 1997, 903. (b) Bruce, M. I. Chem.
Rev. 1998, 98, 2797. (c) Cadierno, V.; Gamasa, M. P.; Gimeno, J . Eur.
J . Inorg. Chem. 2001, 571. (d) Esteruelas, M. A.; Lo´pez, A. M. In Recent
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(3) Selegue, J . P. Organometallics 1982, 1, 217.
10.1021/om020652r CCC: $25.00 © 2003 American Chemical Society
Publication on Web 12/07/2002

New N-Heterocyclic Ruthenium Derivatives
Organometallics, Vol. 22, No. 1, 2003 163
Sch em e 1
bonds of primary and secondary amines to give second-
ary, [Ru(η5-C5H5){C(CHdCPh2)dN(R)H}(CO)(PiPr3)]BF4
(R ) nPr, Ph), and tertiary, [Ru(η5-C5H5){C(CHdCPh2)d
F igu r e 1. Molecular diagram for the complex Ru(η5-C5H5)-
{4-methylidene-6,6-diphenyl-2-azabicyclo[3.1.0]hex-2-en-1-
yl}(CO)(PiPr3) (3). Thermal ellipsoids are shown at the 50%
probability level.
NR2}(CO)(PiPr3)]BF4 (NR2 ) NEt2, NCH2(CH2)3CH2),
azoniabutadienyl derivatives. In the presence of bases
there is a marked difference in behavior between them.
Treatment of [Ru(η5-C5H5){C(CHdCPh2)dN(R)H}(CO)(Pi-
Pr3)]BF4 with sodium methoxide results in the depro-
tonation of the nitrogen atom and the formation of the
corresponding azabutadienyl derivatives Ru(η5-C5H5)-
{C(CHdCPh2)dNR}(CO)(PiPr3). Under the same condi-
tions, the deprotonation of [Ru(η5-C5H5){C(CHdCPh2)d
NR2}(CO)(PiPr3)]BF4 occurs at the CHdCPh2 group and,
as a consequence, the aminoallenyl compounds Ru(η5-
C5H5){C(NR2)dCdCPh2}(CO)(PiPr3) are formed.10
The hydroamination of unsaturated organic molecules
in the presence of transition-metal complexes is an
attractive route to prepare numerous classes of organo-
nitrogen molecules.11 In an effort to develop new meth-
ods of synthesis of organometallic compounds containing
new types of organic nitrogen ligands, we have studied
the reactivity of the allenylidene complex [Ru(η5-C5H5)-
(dCdCdCPh2)(CO)(PiPr3)]BF4 toward primary and sec-
ondary propargylamines.
the formation of the bicyclic complex Ru(η5-C5H5){4-
methylidene-6,6-diphenyl-2-azabicyclo[3.1.0]hex-2-en-1-
yl}(CO)(PiPr3) (3) as a result of a double C-C coupling,
the CR and Cγ atoms of the allenylidene of 1 and the Câ
atom of the allenylidene with the Câ atom of the
propargylamine (Scheme 1).
Complex 2 was isolated as a yellow solid in 94% yield.
Its spectroscopic data strongly support the formation
of the secondary azoniabutadienyl ligand. The IR spec-
trum in Nujol shows a ν(NH) band at 3361 cm-1, along
with ν(tCH), ν(CtC), and ν(CdN) absorptions at 3256,
2120, and 1598 cm-1, respectively. In the 1H NMR
spectrum in chloroform-d, the dNH resonance is ob-
served at 9.83 ppm as a broad signal, whereas the d
CH resonance appears at 6.67 ppm as a singlet. The
propargylic unit gives rise to two double doublets of
doublets at 4.55 and 4.42 (CH2) ppm and a double
doublet at 2.37 (CH) ppm with H-H coupling constants
of 16.8 (2J ), 4.8 (3J ), and 2.1 Hz (4J ). In the 13C{1H}
NMR spectrum, the resonance due to the CdN carbon
atom appears at 247.9 ppm as a doublet with a C-P
coupling constant of 10.5 Hz, whereas the dCPh2 and
dCH resonances are observed at 142.5 and 133.3 ppm
as singlets. The propargylic carbon atoms display sin-
glets at 75.8 (Ct), 74.0 (tCH), and 40.1 ppm (CH2). The
31P{1H} NMR spectrum contains a singlet at 62.4 ppm.
These spectroscopic data agree with those previously
reported for the complexes [Ru(η5-C5H5){C(CHdCPh2)d
In this paper, we report the discovery of novel reaction
patterns in the chemistry of the transition-metal-
allenylidene complexes and three novel types of orga-
nometallic compounds with the nitrogen-heterocyclic
ligands 2-azabicyclo[3.1.0]hex-2-enyl, dihydropyridini-
umyl, and dihydronaphthopyrrolyl.
Resu lts a n d Discu ssion
1. Rea ction of [Ru (η5-C5H5)(dCdCdCP h 2)(CO)-
(P iP r 3)]BF 4 w ith P r op a r gyla m in e: F or m a tion of
R u (η5-C5H 5){4-m et h ylid en e-6,6-d ip h en yl-2-a za b i-
cyclo[3.1.0]h ex-2-en -1-yl}(CO)(P iP r 3). Similarly to
propylamine and aniline, one of the N-H bonds of
propargylamine is added to the CR-Câ double bond of
the allenylidene ligand of [Ru(η5-C5H5)(CdCdCPh2)(CO)-
(PiPr3)]BF4 (1). Thus, at room temperature, the addition
of 1.1 equiv of the amine to the dichloromethane
solutions of 1 leads to the secondary azoniabutadienyl
derivative [Ru(η5-C5H5){C(CHdCPh2)dNHCH2CtCH)}-
(CO)(PiPr3)]BF4 (2). Treatment at room temperature of
2 with KOH in methanol produces its deprotonation and
n
N(R)H}(CO)(PiPr3)]BF4 (R ) Pr, Ph).10
Complex 3 was isolated as a yellow solid in 51% yield.
Figure 1 shows a view of the molecular geometry of this
compound. Selected bond distances and angles are listed
in Table 1.
The geometry around the ruthenium center is close
to octahedral, with the cyclopentadienyl ligand occupy-
ing three sites of a face. The angles formed by the
triisopropylphosphine, the carbonyl, and the η1-carbon
ligand are all close to 90°. The bicycle contains an
exocyclic C-C double bond (C(4)-C(5) ) 1.319(3) Å),
and its skeleton can be described as a cyclopropane
fused with a 1-pyrroline (N-C(3) ) 1.273(3) Å). The five-
membered cycle is almost planar and forms a dihedral
angle of 71.92(13)° with the three-membered ring. The
(10) Bernad, D. J .; Esteruelas, M. A.; Lo´pez, A. M.; Modrego, J .;
Puerta, M. C.; Valerga, P. Organometallics, 1999, 18, 4995.
(11) Mu¨ller, T. E.; Beller, M. Chem. Rev. 1998, 98, 675.

164 Organometallics, Vol. 22, No. 1, 2003
Buil et al.
Ta ble 1. Selected Bon d Len gth s (Å) a n d An gles
(d eg) for Ru (η5-C5H5){4-m eth ylid en e-6,6-
d ip h en yl-2-a za bicyclo[3.1.0]h ex-2-en -1-yl}(CO)-
(P iP r 3) (3)
complex 4 isomerizes into 3 in quantitative yield after
4 h.
Ru-P
2.3283(6)
2.118(2)
2.260(2)
2.266(2)
2.267(2)
2.252(2)
2.251(2)
1.828(2)
N-C(1)
1.470(3)
1.273(3)
1.530(3)
1.551(3)
1.532(3)
1.477(3)
1.473(3)
1.319(3)
Ru-C(1)
Ru-C(28)
Ru-C(29)
Ru-C(30)
Ru-C(31)
Ru-C(32)
Ru-C(33)
N-C(3)
C(1)-C(2)
C(1)-C(6)
C(2)-C(6)
C(2)-C(4)
C(3)-C(4)
C(4)-C(5)
Complex 4 was isolated as a white solid in 75% yield.
In the H NMR spectrum of this compound in dichlo-
1
Ma-Ru-P
M-Ru-C(1)
M-Ru-C(33)
P-Ru-C(1)
P-Ru-C(33)
C(1)-Ru-C(33)
Ru-C(1)-N
Ru-C(1)-C(2)
Ru-C(1)-C(6)
N-C(1)-C(2)
127.95(7)
118.57(9)
124.75(10)
93.55(6)
88.14(7)
94.84(9)
112.34(14)
132.15(15)
127.36(14)
105.30(17)
N-C(1)-C(6)
109.63(17)
115.8(2)
N-C(3)-C(4)
romethane-d2, the most noticeable feature is the absence
of any NH resonance. The presence of a propargylic unit
is strongly supported by the CH2 and tCH resonances,
which are observed as an AB spin system (δ 4.26, ∆ν )
33.2 Hz, J A-B ) 16.5 Hz) and a singlet (δ 2.26),
respectively. The dCH resonance appears at 6.63 ppm,
as a singlet. In the 13C{1H} NMR spectrum, the prop-
argylic unit displays three singlets at 83.0 (Ct), 70.6
(tCH), and 45.8 (CH2) ppm, whereas the Ru-C carbon
atom gives rise to a doublet at 204.2 ppm, with a C-P
coupling constant of 12.1 Hz. The resonances corre-
sponding to the dCH and dCPh2 carbon atoms appear
as singlets at 140.3 and 133.1 ppm. The 31P{1H} NMR
spectrum shows a singlet at 66.0 ppm.
C(1)-N-C(3)
109.16(18)
60.84(14)
59.52(14)
59.64(14)
103.30(18)
130.2(2)
C(1)-C(2)-C(6)
C(1)-C(6)-C(2)
C(2)-C(1)-C(6)
C(2)-C(4)-C(3)
C(2)-C(4)-C(5)
C(3)-C(4)-C(5)
126.4(2)
a
M represents the midpoint of the C(28)-C(32) Cp ligand.
Sch em e 2
The direct participation of methanol in the formation
of 3, catalyzing the propargylic-allenic isomerization is
strongly supported by the formation of a 1:1 isomeric
mixture of 3a -d and 3b-d (eq 2) when complex 4 is
stirred in methanol-d4 over 4 h.
bicycle is bonded to the ruthenium by a single bond
through one of the ring junction carbon atoms (Ru-C(1)
) 2.118(2) Å).
1
The H and 13C{1H} NMR spectra of 3 are consistent
with the formation of the bicycle. In the 1H NMR
spectrum in benzene-d6, the resonances corresponding
to the vinylic proton of the pyrroline unit, the protons
of the exocyclic CH2 group, and the proton bonded to
the ring junction C(2) atom are observed as singlets at
6.80, 5.20 and 4.91, and 3.14 ppm, respectively. In the
13C{1H} NMR spectrum, the Ru-C carbon atom gives
rise to a doublet at 62.8 ppm with a C-P coupling
constant of 10.1 Hz. The C(2), C(3), C(4), C(5), and C(6)
atoms of the bicycle display singlets at 42.7, 157.8,
156.5, 108.5, and 57.8 ppm, respectively. The 31P{1H}
NMR spectrum shows a singlet at 64.5 ppm.
The formation of the bicycle from the unsaturated η1-
carbon donor ligand of 2 is a three-elemental-step
reaction involving: (i) deprotonation of the nitrogen
atom, (ii) propargylic to allenic isomerization catalyzed
by the solvent (methanol), and (iii) double intramolecu-
lar C-C coupling (Scheme 2).
The presence of a deuterium atom at each side of the
1
exocyclic C-C double bond is inferred from the H and
1
2H NMR spectra of the isomeric mixture. The H NMR
spectrum shows two singlets at 5.20 and 4.90 ppm with
2
a 0.5:0.5 intensity ratio, whereas the H NMR spectrum
contains two broad singlets at 5.22 and 4.98 ppm.
The deprotonation of 2 and the double intramolecular
C-C coupling are the fast steps in the formation of 3,
while the propargylic to allenic rearrangement appears
to be the slow step of the reaction. In agreement with
this, all attempts to isolate the allenic intermediate were
unsuccessful.
In addition, it should be noted that the formation of
the three-membered ring of 3 involves a novel intramo-
lecular cyclopropanation, which has no precedent in the
allenylidene chemistry. The fact that the propargyl-
azabutadienyl derivative 4 is stable in the absence of
methanol suggests that the cyclopropanation process is
induced by the allenic unit and involves the initial
nucleophilic attack of the central carbon atom of the
unsaturated Ru-C3 chain at the central carbon atom
of the allenic unit (Scheme 2).
In agreement with this proposal, we have observed
that the treatment at room temperature of 2 with
sodium methoxide in tetrahydrofuran affords Ru(η5-
C5H5){C(CHdCPh2)dNCH2CtCH)}(CO)(PiPr3) (4), as
a result of the deprotonation of the nitrogen atom of 2
(eq 1), and that in methanol at room temperature

New N-Heterocyclic Ruthenium Derivatives
Organometallics, Vol. 22, No. 1, 2003 165
Intermolecular cyclopropanation reactions have re-
ceived predominant attention in the chemistry of car-
bene complexes.12 The intramolecular formation of
three-membered rings from vinylidene starting com-
pounds has been also observed. Thus, we note that the
addition of [NnBu4]OH to cationic vinylidene compounds
of the type [Ru(η5-C5H5){dCdC(R)CH2R′}(PPh3)2]+ af-
fords cyclopropenyl derivatives, where, in contrast to 3,
the three-membered ring is unsaturated.13
2. Rea ction of [Ru (η5-C5H5)(dCdCdCP h 2)(CO)-
(P iP r 3)]BF 4 w ith 1,1-Dieth ylp r op a r gyla m in e: F or -
m ation of [Ru (η5-C5H5)(2,2-dieth yl-5-diph en yliden e-
2,5-d ih yd r op yr id in iu m -6-yl)(CO)(P iP r 3)]BF 4. The
propargylic-allenic isomerization involves a 1,3-hydro-
gen shift within the substituent of the amine. To block
this process, we have carried out the reaction of 1 with
1,1-diethylpropargylamine, which does not contain hy-
drogen atoms in R-positions with regard to the nitrogen
atom. Unexpectedly, the treatment at room temperature
of 1 with 1.2 equiv of 1,1-diethylpropargylamine in
dichloromethane led to the dihydropyridiniumyl deriva-
tive [Ru(η5-C5H5)(2,2-diethyl-5-diphenylidene-2,5-dihy-
dropyridinium-6-yl)(CO)(PiPr3)]BF4 (5). This reaction,
without precedent in the organometallic chemistry,
involves the selective N,Cγ addition of the amine to the
CR-Câ double bond of the allenylidene ligand of 1 (eq
3).
F igu r e 2. Molecular diagram of the cation of [Ru(η5-C5H5)-
(2,2-diethyl-5-diphenylidene-2,5-dihydropyridinium-6-yl)-
(CO)(PiPr3)]BF4 (5). Thermal ellipsoids are shown at the
50% probability level.
Ta ble 2. Selected Bon d Len gth s (Å) a n d An gles
(d eg) for [Ru (η5-C5H5)(2,2-d ieth yl-5-d ip h en ylid en e-
2,5-d ih yd r op ir id in iu m -6-yl)(CO)(P iP r 3)]BF 4 (5)′
Ru-P
2.3560(10)
2.033(3)
1.829(3)
2.250(3)
2.234(3)
2.230(3)
2.262(3)
2.261(3)
N-C(1)
1.313(4)
1.504(4)
1.502(4)
1.475(4)
1.351(4)
1.316(4)
1.511(4)
Ru-C(1)
Ru-C(32)
Ru-C(33)
Ru-C(34)
Ru-C(35)
Ru-C(36)
Ru-C(37)
N-C(5)
C(1)-C(2)
C(2)-C(3)
C(2)-C(10)
C(3)-C(4)
C(4)-C(5)
Ma-Ru-P
125.18(10)
124.41(13)
121.65(15)
92.18(9)
91.24(10)
92.89(13)
123.2(2)
N-C(1)-C(2)
111.6(3)
105.8(3)
112.9(3)
123.6(3)
118.6(3)
120.4(3
M-Ru-C(1)
M-Ru-C(32)
P-Ru-C(1)
P-Ru-C(32)
C(1)-Ru-C(32)
Ru-C(1)-N
Ru-C(1)-C(2)
N-C(5)-C(4)
C(1)-C(2)-C(3)
C(1)-C(2)-C(10)
C(2)-C(3)-C(4)
C(3)-C(4)-C(5)
C(3)-C(2)-C(10)
123.2(3)
125.0(2)
a
M represents the midpoint of the C(33)-C(37) Cp ligand.
C(2)-C(10) (1.351(4) Å) exocyclic double bond. The latter
is disposed in a para position with regard to the
disubstituted C(5) carbon atom and in an ortho position
with regard to the Ru-C(1) bond (2.033(3) Å), which is
in a position R to the nitrogen atom. The N-C(1) bond
length compares well with the N-C double-bond length
found in [Ru(η5-C5H5){C(CHdCPh2)dNEt2}(CO)(PiPr3)]-
BF4 (1.306(7) Å), Schiff bases, hydrazones, and related
compounds.10 The Ru-C(1) distance lies between those
reported for the allenyl derivatives Ru(η5-C5H5){C(Ct
CPh)dCdCPh2}(CO)(PiPr3) (2.004(5) Å)8b and [Ru(η5-
C5H5){C(PHPh2)dCdCPh2}(CO)(PiPr3)]BF4 (2.139(5) Å),8e
where a Ru-C(sp2) single bond is proposed to exit.
In agreement with the structure shown in Figure 2,
the IR spectrum shows a ν(NH) band at 3323 cm-1. In
Complex 5 was isolated as a yellow solid in 65% yield
1
and characterized by elemental analysis, IR and H, 13C-
{1H}, and 31P{1H} NMR spectroscopy, and X-ray dif-
fraction analysis. Figure 2 shows a view of the cation
of this compound. Selected bond distances and angles
are listed in Table 2.
The geometry around the ruthenium center is close
to octahedral, with the cyclopentadienyl ligand occupy-
ing three sites of a face. The angles formed by the
triisopropylphosphine, the carbonyl, and the heterocycle
are all close to 90°.
The heterocycle contains endocyclic N-C(1) (1.313-
(4) Å) and C(3)-C(4) (1.316 (4) Å) double bonds and a
1
the H NMR spectrum at room temperature in chloro-
(12) For example: (a) Brookhart, M.; Studabaker, W. B. Chem. Rev.
1987, 87, 411. (b) Casey, C. P.; Hornung, N. L.; Kosar, W. P. J . Am.
Chem. Soc. 1987, 109, 4908. (c) Wulff, W. D. In Comprehensive Organic
Synthesis; Trost, B. M., Fleming, I., Eds.; Pergamon: New York, 1991;
Vol. 5. (d) Buchert, M.; Reissig, H.-U. Chem. Ber. 1992, 125, 2723. (e)
Doyle, M. D.; Forbes, D. C. Chem. Rev. 1998, 98, 911. (f) Barluenga,
J .; Lo´pez, S.; Ferna´ndez-Acebes, A.; Trabanco, A. A.; Flo´rez, J . J . Am.
Chem. Soc. 2000, 122, 8145. (g) Che, C.-M.; Huang, J .-S.; Lee, F.-W.;
Li, Y.; Lai, T.-S.; Kwong, H.-L.; Teng, P.-F.; Lee, W.-S.; Lo, W.-C.; Peng,
S.-M.; Zhou, Z.-Y. J . Am. Chem. Soc. 2001, 123, 4119. (h) Li, Y.; Huang,
J .-S.; Zou, Z.-Y.; Che, C.-M. J . Am. Chem. Soc. 2001, 123, 4843.
(13) Ting, P. C.; Lin, Y.-C.; Lee, G.-H.; Cheng, M.-C.; Wang, Y. J .
Am. Chem. Soc. 1996, 118, 6433.
form-d, the NH resonance is observed at 9.61 ppm, as
a broad signal. In addition, we should mention two
doublets with a H-H coupling constant of 9.6 Hz, at
6.30 and 5.75 ppm, corresponding to the olefinic protons
of the endocyclic C(3)-C(4) double bond. In the 13C{1H}
NMR spectrum, the resonance due to C(1) appears at
237.4 ppm, as a doublet with a C-P coupling constant
of 9.8 Hz, whereas the C(sp2) atoms C(2), C(3), C(4), and
C(10) display singlets at 147.7, 136.4, 131.5, and 142.8

166 Organometallics, Vol. 22, No. 1, 2003
Buil et al.
Sch em e 3
nances appear at 6.70 (6b) and 6.60 ppm (6a ) as
singlets, whereas the N-methylpropargyl units display
a doublet (CH2, J H-H ) 2.1 Hz) at 5.01 ppm (6a and
4
6b), two singlets (CH3) at 3.80 (6b) and 3.72 ppm (6a ),
and a triplet (tCH) at 2.64 ppm (6a and 6b). In the
13C{1H} NMR spectrum, the resonances corresponding
to the Ru-CR atoms are observed at 244.0 (6a ) and
243.6 ppm (6b), as doublets with C-P coupling con-
stants between 9 and 10 Hz, whereas the dCH and d
CPh2 resonances appear at 138.3 (6a ) and 137.1 ppm
(6b) and at 141.4 (6a ) and 140.6 (6b), respectively, as
singlets. The propargylic units display singlets, for 6a
at 77.1 (tCH), 75.7 (Ct), and 53.8 ppm (CH2) and for
6b at 76.8 (tCH), 74.8 (Ct) and 43.6 ppm (CH2). The
31P{1H} NMR spectrum contains two singlets at 63.1
(6a ) and 62.6 ppm (6b).
Treatment at -78 °C of the tetrahydrofuran solutions
of the isomeric mixture of 6 with 2.0 equiv of sodium
methoxide affords after 40 min a 1:1 mixture of the
dihydronaphthopyrrolyl diastereomers (RRuSC,SRuRC)-
[Ru(η5-C5H5){9-phenyl-4,4a-dihydronaphtho[2,3-c]-1-
pyrrolyl}(CO)(PiPr3) (7a ) and (RRuRC,SRuSC)-[Ru(η5-
C5H5){9-phenyl-4,4a-dihydronaphtho[2,3-c]-1-pyrro-
lyl}(CO)(PiPr3) (7b) according to the 1H and 31P{1H}
NMR spectra of the crude reaction product. The isomeric
mixture was isolated as a yellow solid in 85% yield (eq
5).
ppm, respectively. The 31P{1H} NMR spectrum contains
a singlet at 60.4 ppm.
The formation of 5 can be rationalized according to
Scheme 3. Because EHT-MO calculations on transition-
metal allenylidene complexes indicate that the CR and
Câ atoms are electrophilic and nucleophilic centers,
respectively,8b,9a,14 it has been proposed that the addition
of amines to the allenylidene ligand of 1 requires an
initial N-CR interaction, which labilizes the N-H
bond.10 In accordance with this, the coordination of the
nitrogen atom of the amine to the CR atom of the
allenylidene of 1, followed by the nucleophilic attack of
the Câ atom at the terminal carbon atom of the prop-
argylic unit, and the subsequent 1,3-hydrogen shift of
one of the NH-hydrogen atoms should give 5.
3. Rea ction of [Ru (η5-C5H5)(dCdCdCP h 2)(CO)-
(P iP r 3)]BF 4 w ith N-Meth ylp r op a r gyla m in e: F or -
m ation of [Ru (η5-C5H5){9-ph en yl-4,4a-dih ydr on aph -
th o[2,3-c]-1-p yr r olyl}(CO)(P iP r 3)]BF 4. In contrast to
1,1-diethylpropargylamine but in agreement with pro-
pargylamine, the N-H bond of N-methylpropargy-
lamine is added to the CR-Câ double bond of the
allenylidene ligand of 1. Thus, at room temperature, the
addition of 1.1 equiv of the amine to dichloromethane
solutions of 1 affords the tertiary azoniabutadienyl
derivative [Ru(η5-C5H5){C(CHdPh2)dN(CH3)CH2CtCH}-
(CO)(PiPr3)]BF4 (6), which was isolated as a yellow solid
in 93% yield. The solid is formed by the isomers 6a and
6b shown in eq 4, in a 7:3 molar ratio.
Microcrystals of 7a were obtained by slow diffusion
of pentane into a concentrated solution of the diaster-
eomeric mixture in toluene and characterized by X-ray
diffraction analysis. The asymmetric unit contains the
enantiomers as two crystallographically independent
molecules. A drawing of both optic isomers is shown in
Figure 3. Selected bond distances and angles are listed
in Table 3.
The geometry around the ruthenium center is like
those of 3 and 5: i.e., close to octahedral with the
cyclopentadienyl ligand occupying three sites of a face.
The angles formed by the triisopropylphosphine, the
carbonyl group, and the polycyclic ligand are all close
to 90°. The polycycle is coordinated to the ruthenium
atom with Ru-C distances of 2.133(2) Å (Ru(1)-C(1))
and 2.107(3) Å (Ru(51)-C(51)), which compare well with
those found in 3 and 5 and support the Ru-C(sp2)
single-bond formulation.
The five-membered rings N(1)-C(4)-C(3)-C(2)-C-
(1) (RRu,SC) and N(51)-C(51)-C(52)-C(53)-C(54) (SRu
-
,RC) are almost planar and aromatic. The aromaticity,
which is the result of the overlap of the filled orbital
containing the lone pair of the nitrogen with the p
orbitals of the adjacent C(sp2) atoms, is strongly sup-
ported by the structural parameters within the rings.
The C(3)-C(4) (1.344(3) Å) and C(53)-C(54) (1.339(4)
Å) distances are in agreement with the sample mean of
carbon-carbon bond length for double bonds (1.32(1)
The formation of both isomeric azoniabutadienyl
1
ligands is strongly supported by the H, 13C{1H}, and
31P{1H} NMR spectra of 6 in chloroform-d at room
1
temperature. In the H NMR spectrum the HCd reso-
(14) (a) Berke, H.; Huttner, G.; Von Seyerl, J . Z. Naturforsch. 1981,
36B, 1277. (b) Cadierno, V.; Gamasa, M. P.; Gimeno, J ., Gonza´lez-
Cueva, M.; Lastra, E.; Borge, J .; Garc´ıa-Granda, S.; Pe´rez-Carren˜o,
E. Organometallics 1996, 15, 2137.

New N-Heterocyclic Ruthenium Derivatives
Organometallics, Vol. 22, No. 1, 2003 167
F igu r e 3. Molecular diagram of the two enantiomers in the asymmetric unit of the complex (RRuSC,SRuRC)-[Ru(η5-C5H5)-
{9-phenyl-3,3a-dihydronaphtho[2,3-c]-1-pyrrolyl}(CO)(PiPr3)] (7a ). Thermal ellipsoids are shown at the 50% probability
level.
Ta ble 3. Selected Bon d Len gth s (Å) a n d An gles (d eg) for
(RRu SC,SRu RC)-Ru (η5-C5H5){9-p h en yl-4,4a -d ih id r on a p h th o(2,3-c)-1-p yr r olyl}(CO)(P iP r 3) (7a )
asymmetric unit
asymmetric unit
R
RuSC
SRuRC
RRuSC
SRuRC
Ru(1)-P(1)
Ru(1)-C(1)
Ru(1)-C(20)
Ru(1)-C(21)
Ru(1)-C(22)
Ru(1)-C(23)
Ru(1)-C(24)
Ru(1)-C(25)
N(1)-C(1)
2.3211(7)
2.133(2)
2.248(3)
2.237(2)
2.247(2)
2.271(2)
2.264(3)
1.822(3)
1.398(3)
1.375(3)
1.444(3)
1.412(3)
2.3568(7)
2.107(3)
2.237(2)
2.277(3)
2.275(3)
2.264(3)
2.223(3)
1.820(3)
1.394(3)
1.372(3)
1.435(3)
1.409(3)
C(2)-C(3)
C(2)-C(6)
C(3)-C(4)
C(3)-C(13)
C(6)-C(7)
C(7)-C(8)
C(7)-C(12)
C(8)-C(9)
C(9)-C(10)
C(10)-C(11)
C(11)-C(12)
C(12)-C(13)
1.434(3)
1.468(3)
1.344(3)
1.494(3)
1.370(3)
1.435(3)
1.527(3)
1.338(3)
1.446(3)
1.325(3)
1.492(3)
1.536(4)
1.434(3)
1.469(3)
1.339(4)
1.491(4)
1.370(3)
1.436(3)
1.525(3)
1.333(3)
1.444(4)
1.326(4)
1.493(4)
1.528(4)
N(1)-C(4)
N(1)-C(5)
C(1)-C(2)
M(1)a-Ru(1)-P(1)
M(1)-Ru(1)-C(1)
M(1)-Ru(1)-C(25)
P(1)-Ru(1)-C(1)
P(1)-Ru(1)-C(25)
C(1)-Ru(1)-C(25)
Ru(1)-C(1)-N(1)
Ru(1)-C(1)-C(2)
N(1)-C(1)-C(2)
N(1)-C(4)-C(3)
C(1)-N(1)-C(4)
C(1)-N(1)-C(5)
C(1)-C(2)-C(3)
C(1)-C(2)-C(6)
126.46(8)
122.64(10)
121.63(11)
93.17(7)
128.85(8)
119.96(10)
124.89(12)
96.94(7)
C(2)-C(3)-C(4)
C(2)-C(3)-C(13)
C(2)-C(6)-C(7)
C(3)-C(13)-C(12)
C(4)-N(1)-C(5)
C(6)-C(7)-C(8)
C(6)-C(7)-C(12)
C(7)-C(8)-C(9)
C(7)-C(12)-C(11)
C(7)-C(12)-C(13)
C(8)-C(9)-C(10)
C(9)-C(10)-C(11)
C(10)-C(11)-C(12)
C(11)-C(12)-C(13)
107.3(2)
121.2(2)
118.5(2)
107.0(2)
120.0(2)
124.7(2)
117.8(2)
122.9(3)
114.9(2)
108.1(2)
121.4(3)
120.3(3)
123.1(2)
112.7(2)
107.2(2)
120.6(2)
117.9(2)
106.7(2)
120.4(2)
125.1(2)
117.9(2)
123.7(3)
114.9(2)
108.0(2)
120.8(3)
120.7(3)
123.0(3)
113.2(2)
88.01(8)
86.46(8)
95.84(10)
120.22(17)
135.27(18)
103.6(2)
108.5(2)
111.5(2)
128.5(2)
108.8(2)
134.9(2)
89.05(11)
124.43(18)
131.58(19)
103.8(2)
108.7(2)
111.4(2)
128.2(2)
108.7(2)
134.1(2)
a
M(1) represents the midpoint of the C(20)-C(24) Cp ligand. The related atoms of the two independent molecules are numbered by n
(RRu,SC) and n + 50 (SRu,RC).
Å).15 The N(1)-C(4) (1.375(3) Å) and N(51)-C(54)
(1.372(3) Å) distances are about 0.02 Å shorter than the
N(1)-C(1) (1.398(3) Å) and N(51)-C(51) (1.394(3) Å)
bond lengths, and all four lie between those found for
the C-N double bonds in 3, 5, Schiff bases, hydrazones,
and related compounds (about 1.29 Å) and those ex-

168 Organometallics, Vol. 22, No. 1, 2003
Buil et al.
Sch em e 4
pected for a C-N single bond such as N(1)-C(5) (1.444-
(3) Å) or N(51)-C(55) (1.435(3) Å). The C(1)-C(2)
(1.412(3) Å) and C(2)-C(3) (1.434(3) Å) distances, and
C(51)-C(52) (1.409(3) Å) and C(52)-C(53) (1.434(3) Å)
distances, are significantly shorter (between 0.03 and
0.06 Å) than the length of a C(sp2)-C(sp2) single bond
(about 1.47 Å). In addition, it should be noted that these
structural parameters show a decrease of bond order,
within the five-membered rings, in the sequences C(3)-
C(4)-N(1)-C(1)-C(2)-C(3) and C(53)-C(54)-N(51)-
C(51)-C(52)-C(53).
The central six-membered ring of both enantiomers
significantly deviates from planarity, showing a boat
conformation with the C(sp3) atom C(13) (RRu,SC) or
C(63) (SRu,RC) away from the bulky triisopropylphos-
phine ligand. The ring contains a C-C double bond,
between the carbon atoms C(6)-C(7) (1.370(3) Å,
RRu,SC) or C(56)-C(57) (1.370(3) Å, SRu,RC).
In contrast to the central six-membered ring, the
outer six-membered ring is almost planar. The bond
lengths in the sequences C(7)-C(8)-C(9)-C(10)-C(11)
(1.435(3), 1.338(3), 1.446(3), 1.325(3) Å) and C(57)-
C(58)-C(59)-C(60)-C(61) (1.436(3), 1.333(3), 1.444(4),
1.326(4) Å) clearly indicate delocalized bonding between
these atoms with the double-bond character mainly
centered on C(8)-C(9) and C(10)-C(11) (RRu,SC) and
C(58)-C(59) and C(60)-C(61) (SRu,RC). The angles
between the planar rings are 30.75(11)°for the RRu,SC
enantiomer and 29.70(12)° for the SRu,RC enantiomer.
tertiary azoniabutadienyl complexes proceeds by extrac-
tion of the proton of the CHdCPh2 group,10 it is
reasonable to assume that one of the key steps of the
process is the formation of an aminoallenyl intermedi-
ate. It is also well-known that bases can catalyze the
isomerization of propargylic into allenic moieties;17
therefore, another key step of the process should be the
isomerization of the aminopropargyl group into ami-
noallenyl. In this context, it should be noted that, under
the conditions of the reaction shown in eq 5, complex 4
is stable. This suggests that the aminopropargyl units
have a higher tendency toward isomerization than the
iminopropargyl units.
The positions of the C-C double bonds within the
polycyclic ligands of both diastereomers are also sup-
ported by the 1H and 13C{1H} NMR spectra of the
isomeric mixture in benzene-d6 at room temperature.
The 1H NMR spectrum shows the resonances corre-
sponding to the triisopropylphosphine and the cyclo-
pentadienyl ligands along with 18 signals, which ac-
The new polycyclic ligand is the result of two carbon-
carbon couplings in 6, the Câ atom of the original C3
chain with the central carbon atom of the propargyl unit
and, at the same time, an ortho carbon atom of one of
the two phenyl groups with the terminal (C(sp)) atom.
These couplings can be rationalized as an intramolecu-
lar Diels-Alder reaction in an allenylamino-dipheny-
lallenyl intermediate, where the Câ-Cγ double bond and
one of the two phenyl groups of the diphenylallenyl
fragment act as an inner-outer ring diene and the Cd
CH2 double bond of the another allenyl fragment acts
as a dienophile. The formation of two diastereomers in
the reaction is the consequence of the chirality of the
ruthenium and the two possible approaches of the
dienophile to the diene.
1
cording to a H-1H COSY NMR spectrum were assigned
as indicated (δ):16 6.93, 6.66 (H8); 6.71, 6.78 (H3); 6.07,
6.02 (H6); 5.97, 5.75 (H5); 5.60, 5.50 (H7); 4.01, 3.97 (H4a);
3.17, 3.78 (CH3); 2.95, 2.90 (H4); 2.69, 2.60 (H4′). In the
13C{1H} NMR spectrum the most noticeable resonances
are 2 doublets at 135.8 (J C-P ) 10.6 Hz) and 134.9 ppm
(J C-P ) 13.8 Hz), assigned to C1, and 14 singlets
assigned according to the 1H-13C HETCOR NMR
spectrum as indicated (δ): 131.1, 130.9 (C5); 127.5, 127.9
(C8); 123.8, 124.2 (C6); 121.1, 118.1 (C3); 119.8, 119.2
(C7); 43.1, 41.9 (C4a); 30.6, 31.1 (C4). The 31P{1H} NMR
spectrum contains two singlets at 63.8 and 63.1 ppm.
Con clu d in g Rem a r k s
This paper gives new evidence of the high potential
of the chemistry of the allenylidene complexes. The
behavior of the allenylidene derivative [Ru(η5-C5H5)(d
CdCdCPh2)(CO)(PiPr3)BF4 toward three different pro-
pargylamines has been studied, and three novel types
of cycloaddition reactions have been discovered, which
have given rise to three novel types of organometallic
compounds.
The formation of 7a and 7b (7) can be rationalized
according to Scheme 4. Since the formation of 7 involves
the deprotonation of 6 (the isomeric mixture of 6a and
6b ) and it is well-known that the deprotonation of
(15) Orpen, A. G.; Brammer, L.; Allen, F. H.; Kennard, O.; Watson,
D. G.; Taylor, R. J . Chem. Soc., Dalton Trans. 1989, S1.
(16)
The new heterocyclic ligands are the result of the
addition of the nitrogen atom of the amine to the CR
atom of the allenylidene and one or two C-C couplings.
The number of new C-C bonds formed depends on both
the nature of the amine (primary or secondary) and the
substituents at the CR atom of the propargyl unit.
(17) Huntsman, W. D. In The Chemistry of Ketenes, Allenes and
Related Compounds; Patai, S., Ed.; Wiley: Chichester, U.K., 1980;
Chapter 15.

New N-Heterocyclic Ruthenium Derivatives
Organometallics, Vol. 22, No. 1, 2003 169
cm-1): ν(CtC) 2022 (w), ν(CO) 1910 (vs), ν(CdN) and ν(CdC)
1594 (w) and 1530 (m). 1H NMR (300 MHz, 223 K, CD2Cl2): δ
7.34-7.10 (m, 10H, Ph), 6.63 (s, 1H, dCH), (s, 5H, Cp), 4.26
(AB system, 2H, ∆ν ) 33.2 Hz, J H-H ) 16.5, CH2), 2.35 (m,
3H, PCHCH3), 2.26 (s, 1H, tCH), 1.26 (dd, 9H, J H-H ) 6.9,
J P-H ) 13.8, PCHCH3), 1.20 (dd, 9H, J H-H ) 7.2, J P-H ) 13.2,
PCHCH3). 13C{1H} NMR (75.4 MHz, 223 K, CD2Cl2): δ 208.2
(d, J P-C ) 18.1, CO), 204.2 (d, J P-C ) 12.1, Ru-C), 143.8, 141.0
(both s, Cipso Ph), 140.3 (s, dCH), 133.1 (s, dCPh2), 130.6, 128.6,
128.5, 128.3, 128.0, 127.2 (all s, Ph), 87.3 (s, Cp), 83.0 (s, Ct
CH), 70.6 (s, CtCH), 45.8 (s, NCH2), 28.0 (d, J P-C ) 23.0,
PCHCH3), 20.8, 19.7 (both s, PCHCH3). 31P{1H} NMR (121.4
MHz, 223 K, CD2Cl2): δ 66.0 (s).
Exp er im en ta l Section
All reactions were carried out with rigorous exclusion of air
using standard Schlenk techniques. Solvents were dried by
known procedures and distilled under argon prior to use. The
starting material [Ru(η5-C5H5){CdCdCPh2)(CO)(PiPr3)]BF4 (1)
was prepared as described in ref 8a. In the NMR spectra,
chemical shifts are expressed in ppm downfield from Me4Si
(1H and 13C) and 85% H3PO4 (31P). Coupling constants, J , are
given in hertz.
P r ep a r a tion of [Ru (η5-C5H5){C(CHdCP h 2)dNHCH2Ct
CH}(CO)(P iP r 3)]BF 4 (2). A deep red solution of [Ru(η5-C5H5)-
(dCdCdCPh2)(CO)(PiPr3)]BF4 (1; 150 mg, 0.24 mmol) in 6 mL
of dichloromethane was treated with propargylamine (18 µL,
0.26 mmol). The mixture was stirred at room temperature for
5 min, and the solution became orange. The solvent was
removed in vacuo, and the residue was treated with 10 mL of
diethyl ether to afford a yellow suspension. The solution was
decanted, and the solid was washed twice with diethyl ether
and dried in vacuo. Yield: 155 mg (94%). Anal. Calcd for
C33H41BF4NOPRu: C, 57.73; H, 6.02; N, 2.04. Found: C, 57.89;
H, 5.90, N, 2.13. IR (Nujol, cm-1): ν(NH) 3361 (m), ν(tCH)
3256 (m), ν(CtC) 2120 (w), ν(CO) 1955 (vs), ν(CdN) and ν-
P r ep a r a tion of th e Isom er ic Mixtu r e of 3a -d a n d 3b-
d . A white suspension of Ru(η5-C5H5){C(CHdCPh2)dNCH2Ct
CH}(CO)(PiPr3) (4; 100 mg, 0.17 mmol) in methanol-d4 was
stirred for 4 h, and the suspension became yellow. The solvent
was removed in vacuo to afford a yellow residue.
1
The H NMR spectrum of the residue shows a 95% yield of
the monodeuterated compound in the dCH2 positions with a
0.5:0.5 intensity ratio.
1
(CdC) 1598 (m) and 1568 (w), ν(BF4) 1030 (br). H NMR (300
2H NMR (C6H6): δ 5.22 (br, dCDH), 4.98 (br, dCHD).
MHz, 293 K, CDCl3): δ 9.83 (br, 1H, NH), 7.45-7.02 (m, 10H,
2
P r ep a r a tion of [Ru (η5-C5H5)(2,2-d ieth yl-5-d ip h en yli-
d en e-2,5-d ih yd r op yr id in iu m -6-yl)(CO)(P iP r 3)]BF 4 (5). A
deep red solution of [Ru(η5-C5H5)(dCdCdCPh2)(CO)(PiPr3)]-
BF4 (1; 350 mg, 0.56 mmol) in 6 mL of dichloromethane was
treated with 1,1-diethylpropargylamine (83 µL, 0.62 mmol).
The mixture was stirred for 30 min, and the solution became
dark yellow. The solvent was removed in vacuo, and the
residue was treated with 6 mL of diethyl ether to afford a
yellow suspension. The solution was decanted, and the solid
was washed twice with diethyl ether, dried in vacuo, and
recrystallized from a dichloromethane-diethyl ether mixture.
Yield: 270 mg (65%). Anal. Calcd for C37H49BF4NOPRu: C,
59.84; H, 6.65; N, 1.88. Found: C, 59.60; H, 6.43; N, 1.80. IR
(Nujol, cm-1): ν(NH) 3323 (m), ν(CO) 1945 (vs), ν(CdN) and
ν(CdC) 1609 (m) and 1530 (w), ν(BF4) 1100 (br). 1H NMR (300
MHz, 293 K, CDCl3): δ 9.61 (br, 1H, NH), 7.40-7.02 (m, 10H,
Ph), 6.30 (d, J H-H ) 9.6, CHd), 5.75 (d, J H-H ) 9.6, CHd),
4.90 (s, 5H, Cp), 2.25 (m, 2H, CH2), 2.13 (m, 3H, PCHCH3),
1.72-1.54 (m, 2H, CH2), 1.19 (dd, 9H, J H-H ) 6.9, J P-H ) 13.8,
PCHCH3), 1.14 (dd, 9H, J H-H ) 7.5, J P-H ) 15.0, PCHCH3),
0.97 (t, 3H, J H-H ) 7.5, CH3), 0.91 (t, J H-H ) 7.2, CH3). 13C
NMR (75.4 MHz, 293 K, CDCl3): δ 237.4 (d, J C-P ) 9.8, Ru-
CR), 205.7 (d, J C-P ) 18.5, CO), 147.7 (s, CdCPh2), 142.8 (s,
dCPh2), 141.3, 141.2 (both s, Cipso), 136.4 (s, CHd), 131.5 (s,
CHd), 130.6, 129.0, 128.9, 128.6, 128.3, 127.8, 126.7 (all s, Ph),
Ph), 6.67 (s, 1H, dCH), 4.89 (s, 5H, Cp), 4.55 (ddd, J H-H
)
)
3
4
2
16.8, J H-H ) 4.8, J H-H ) 2.1, 1H, CH2), 4.42 (ddd, J H-H
3
4
4
16.8, J H-H ) 6.9, J H-H ) 2.1, 1H, CH2), 2.37 (dd, J H-H
4
) J ′H-H ) 2.1, 1H, tCH), 2.23 (m, 3H, PCHCH3), 1.28 (dd,
9H, J H-H ) 6.9, J P-H ) 13.5, PCHCH3), 1.27 (dd, 9H, J H-H
)
7.2, J P-H ) 14.7, PCHCH3). 13C{1H} NMR (75.4 MHz, 293 K,
CDCl3): δ 247.9 (d, J P-C ) 10.5, Ru-C), 204.1 (d, J P-C ) 16.6,
CO), 142.5 (s, dCPh2), 141.0, 138.6 (both s, Cipso Ph), 133.3 (s,
dCH), 130.5, 129.1, 128.6, 128.5, 128.3 (all s, Ph), 86.9 (s, Cp),
75.8 (s, CtCH), 74.0 (s, CtCH), 40.1 (s, NHCH2), 28.7 (d, J P-C
) 23.8, PCHCH3), 20.1, 19.4 (both s, PCHCH3). 31P{1H} NMR
(121.4 MHz, 293 K, CDCl3): δ 62.4 (s).
P r ep a r a tion of Ru (η5-C5H5){4-m eth ylid en e-6,6-d ip h e-
n yl-2-a za bicyclo[3.1.0]h ex-2-en -1-yl}(CO)(P iP r 3) (3). A yel-
low suspension of 2 (500 mg, 0.73 mmol) in 10 mL of methanol
was treated with an excess of KOH (100 mg, 1.78 mmol) and
stirred at room temperature for 4 h. The mixture became
green, and the solvent was removed in vacuo. Dichloromethane
was added, and the suspension was filtered to remove potas-
sium tetrafluoroborate. Solvent was evaporated, and the
residue was washed three times with methanol to afford a
yellow solid, which was dried in vacuo. Yield: 223 mg (51%).
Anal. Calcd for C33H40NOPRu: C, 66.20; H, 6.73; N, 2.34.
Found: C, 65.90; H, 6.26, N, 2.21. IR (Nujol, cm-1): ν(CO) 1913
(vs), ν(CdN) and ν(CdC) 1624 (w) and 1595 (m). 1H NMR (300
MHz, 293 K, C6D6): δ 7.51-6.94 (m, 10H, Ph), 6.80 (s, 1H,
NdCH), 5.20 (s, 1H, dCH2), 4.98 (s, 5H, Cp), 4.91 (s, 1H, d
CH2), 3.14 (s, 1H, CH), 1.96 (m, 3H, PCHCH3), 1.04 (dd, 9H,
J H-H ) 7.2, J P-H ) 14.1, PCHCH3), 0.91 (dd, 9H, J H-H ) 7.1,
J P-H ) 12.1, PCHCH3). 13C{1H} NMR (75.4 MHz, 293 K, C6D6,
plus APT, plus HETCOR): δ 208.7 (d, J P-C ) 20.2, CO), 157.8
(s, NdCH), 156.5 (s, CdCH2), 147.4, 143.1 (both s, Cipso Ph),
134.3, 130.3, 127.6, 125.3, 125.2 (all s, Ph), 108.5 (s, dCH2),
86.8 (s, Cp), 62.8 (d, J P-C ) 10.1, Ru-C), 57.8 (s, CPh2), 42.7
(s, CH), 26.8 (d, J P-C ) 20.7, PCHCH3), 20.6, 19.3 (both s,
PCHCH3). 31P{1H} NMR (121.4 MHz, 293 K, C6D6): δ 64.5 (s).
P r ep a r a t ion of R u (η5-C5H 5){C(CH dCP h 2)dNCH 2Ct
CH}(CO)(P iP r 3) (4). A brown solution of 2 (150 mg, 0.22
mmol) in 10 mL of THF was treated with sodium methoxide
(28.9 mg, 0.54 mmol) and stirred at room temperature for 5
h. The solvent was removed in vacuo. Toluene was added, and
the suspension was filtered to remove sodium tetrafluorobo-
rate. Solvent was evaporated, and the residue was washed
with pentane to afford a white solid, which was dried in vacuo.
Yield: 91 mg (70%). Anal. Calcd for C33H40NOPRu: C, 66.20;
H, 6.73; N, 2.34. Found: C, 66.54; H, 6.54, N, 2.21. IR (Nujol,
86.8 (s, Cp), 69.6 (s, C(Et)2), 29.1 (s, CH2), 27.9 (d, (d, J C-P
)
23.1, PCHCH3), 26.8 (s, CH2), 20.1, 19.0 (both s, PCHCH3),
8.7, 8.2 (both s, CH3).
P r ep a r a t ion of [R u (η5-C5H 5){C(CH dCP h 2)dN(CH 3)-
CH2CtCH}(CO)(P iP r 3)]BF 4 (6). A deep red solution of [Ru-
(η5-C5H5)(dCdCdCPh2)(CO)(PiPr3)]BF4 (1; 150 mg, 0.24 mmol)
in 6 mL of dichloromethane was treated with N-methylprop-
argylamine (22 µL, 0.26 mmol). The mixture was stirred for
15 min, and the solution became dark orange. The solvent was
removed in vacuo, and the residue was treated with 6 mL of
diethyl ether to afford a pale yellow suspension. The solution
was decanted, and the solid was washed twice with diethyl
ether and dried in vacuo. The solid obtained was a mixture of
two isomers, 6a and 6b, in a 7:3 molar ratio. Yield: 156 mg
(93%). Anal. Calcd for C34H43BF4NOPRu: C, 58.30; H, 6.19;
N, 2.0. Found: C, 57.92; H, 6.08; N, 2.18. IR (Nujol, cm-1):
ν(tCH) 3524 (m), ν(CtC) 2123 (w), ν(CO) 1964 (vs), ν(CdN)
and ν(CdC) 1599 (m) and 1550 (w), ν(BF4) 1064 (br).

170 Organometallics, Vol. 22, No. 1, 2003
Ta ble 4. Cr ysta l Da ta a n d Da ta Collection a n d Refin em en t Deta ils for 3, 5, a n d 7a
Buil et al.
3
5
7a
Crystal Data
formula
C33H40NOPRu
598.70
monoclinic, P21/n
11.2753(5)
13.6961(6)
17.9585(7)
C37H49BF4NOPRu
742.62
monoclinic, P21/n
14.9386(12)
11.9727(10)
20.7213(16)
C34H42NOPRu
612.73
mol wt
symmetry, space group
triclinic, P1h
12.6201(7)
14.6901(8)
16.5516(9)
70.624(1)
82.439(1)
81.567(1)
2852.1(3)
4
a, Å
b, Å
c, Å
R, deg
â, deg
γ, deg
V, Å3
Z
94.062(1)
106.129(2)
2766.3(2)
4
1.438
3560.2(5)
4
1.385
Dcalcd, g cm-3
1.427
Data Collection and Refinement Details
Bruker Smart APEX
diffractometer
λ(Mo KR), Å
0.710 73
graphite oriented
ω scans
monochromator
scan type
µ, mm-1
0.652
0.536
0.634
3, 56
100
2θ range, deg
3, 56
100
3, 56
temp, K
100
no. of data collected
no. of unique data
no. of params/restraints
R1a (F2 > 2σ(F2))
wR2b (all data)
Sc (all data)
33 352
24 356
35 094
6699 (Rint ) 0.0629)
8310 (Rint ) 0.0670)
13 312 (Rint ) 0.0386)
356/0
435/0
723/0
0.0321
0.0433
0.0341
0.0618
0.824
0.0656
0.0605
0.961
0.727
R1(F) ) ∑||Fo| - |Fc||/∑|Fo|. wR2(F2)){∑[w(Fo2 - Fc2)2]/∑[w(Fo2)2]}1/2
.
c GOF ) S ) {∑[(Fo2 - Fc2)2]/(n - p)}1/2, where n is the number
a
b
of reflections and p is the number of refined parameters.
NMR data for isomer 6a : 1H NMR (300 MHz, 293 K, CDCl3)
δ 7.49-7.01 (m, 10H, Ph), 6.60 (s, 1H, dCH), 5.01 (d, 2H, 4J H-H
) 2.1, CH2), 4.78 (s, 5H, Cp), 3.72 (s, 3H, CH3), 2.64 (d, 1H,
4J H-H ) 2.1, tCH), 2.40 (m, 3H, PCHCH3), 1.29-1.20 (m, 18H,
PCHCH3); 13C NMR (75.4 MHz, 293 K, CDCl3) δ 244.0 (d, J C-P
) 9.8, Ru-CR), 204.0 (d, J C-P ) 17.4, CO), 141.4 (s, dCPh2),
139.1, 138.6 (both s, Cipso), 138.3 (s, dCH), 130.4, 129.1, 128.8,
128.5, 128.4 (all s, Ph), 86.3 (s, Cp), 77.1 (s, CtCH), 75.7 (s,
CtCH), 53.8 (s, NCH2), 43.6 (NCH3), 28.4 (d, J C-P ) 23.3,
PCHCH3), 19.9 (s, PCHCH3); 31P{1H} NMR (121.4 MHz, 293
K, CDCl3) δ 63.1 (s).
NMR data for isomer 6b: 1H NMR (300 MHz, 293 K, CDCl3)
δ 7.49-7.01 (m, 10H, Ph), 6.70 (s, 1H, dCH), 5.01 (d, 2H, 4J H-H
) 2.1, CH2), 4.72 (s, 5H, Cp), 3.80 (s, 3H, CH3), 2.64 (d, 1H,
4J H-H ) 2.1, tCH), 2.31 (m, 3H, PCHCH3), 1.29-1.20 (m, 18H,
PCHCH3); 13C NMR (75.4 MHz, 293 K, CDCl3) δ 243.6 (d, J C-P
) 9.1, Ru-CR), 204.2 (d, J C-P ) 18.1, CO), 141.5 (s, dCPh2),
140.6, 138.5 (both s, Cipso), 137.1 (s, dCH), 130.6, 129.1, 128.9,
128.4, (all s, Ph), 86.7 (s, Cp), 76.1 (s, CtCH), 74.8 (s, Ct
CH), 49.5 (s, NCH3), 43.6 (NCH2), 28.5 (d, J C-P ) 23.1,
PCHCH3), 19.8 (s, PCHCH3); 31P{1H} NMR (121.4 MHz, 293
K, CDCl3) δ 62.6 (s).
1H, J H
) J H
) 14.4, H4), 2.69 (dd, 1H, J H
) 14.4,
-H
-H
-H
4
4
4a
4¢
4
J H
4′) 4.5, H4′), 1.85 (m, 3H, PCHCH3), 0.76 (dd, 9H, J H-H
-H
4′
4a
) 6.9, J P-H ) 12.9, PCHCH3), 0.75 (dd, 9H, J H-H ) 7.2, J P-H
) 14.1, PCHCH3); 13C{1H} NMR (75.4 MHz, 293 K, C6D6, plus
HETCOR) δ 211.1 (d, J P-C ) 24.4, CO), 134.9 (d, J P-C ) 13.8,
C1), 143.7, 139.4, 137.6, 129.4, 121.1 (all s, Cipso-Ph, C3a, C8a
,
C9, C9a), 132.7, 127.1, 126.5 (all s, Ph), 131.1 (s, C5), 127.5 (s,
C8), 123.8 (s, C6), 121.1 (s, C3), 119.8 (s, C7), 85.8 (s, Cp), 43.1
(s, C4a), 41.4 (s, C3), 30.6 (s, C4), 28.5 (d, J P-C ) 21.6, PCHCH3),
21.1 and 20.4 (both s, PCHCH3).
1H and 13C{1H} NMR data for the other diastereoisomer:
1H NMR (300 MHz, 293 K, C6D6) δ 7.16-6.98 (m, 5H, Ph),
6.66 (d, 1H, J H
H6), 5.75 (dd, 1H, J (H5-H6) ) 9.3 Hz, J H
5.50 (m, 1H, H7), 4.27 (s, 5H, Cp), 3.97 (m, 1H, H4a), 3.78 (s,
3H, CH3), 2.90 (dd, 1H, J H ) J H ) 14.7, H4), 2.60 (dd,
) 9.9, H8), 6.78 (s, 1H, H3), 6.02 (m, 1H,
-H
7
8
) 4.5 Hz, H5),
-H
4a
5
-H
-H
4a
4′
4
4
1H, J H
) 14.1, J H
) 4.2, H4′), 2.12 (m, 3H, PCHCH3),
-H
-H
4a
4′
4
4′
0.91 (dd, 9H, J H-H ) 7.2, J P-H ) 14.1, PCHCH3), 0.85 (dd, 9H,
J H-H ) 6.9, J P-H ) 13.8, PCHCH3); 13C{1H} NMR (75.4 MHz,
293 K, C6D6, plus HETCOR) δ 208.9 (d, J P-C ) 22.6, CO), 135.8
(d, J P-C ) 10.6, C1), 143.7, 140.4, 138.3, 128.9, 119.8 (all s,
P r ep a r a tion of [Ru (η5-C5H5){9-p h en yl-4,4a -d ih yd r o-
n a p h th o[2,3-c]-1-p yr r olyl}(CO)(P iP r 3)]BF 4 (7). A pale yel-
low solution of [Ru(η5-C5H5){C(CHdCPh2)dN(CH3)CH2CtCH}-
(CO)(PiPr3)]BF4 (6; 250 mg, 0.36 mmol) in 10 mL of tetrahydro-
furan at -78 °C was treated with sodium methoxide (39 mg,
0.71 mmol). The mixture was stirred for 40 min, and the color
changed to bright yellow. Solvent was evaporated to dryness.
Pentane was added, the suspension was filtered to eliminate
sodium tetrafluoroborate, and the solution was recovered at
-78 °C. Solvent was evaporated in vacuo to afford a bright
yellow solid. The solid obtained was a mixture of two diaster-
eomers in a 1:1 molar ratio. Yield: 188 mg (85%). Anal. Calcd
for C34H42NOPRu: C, 66.50; H, 7.06; N, 2.28. Found: C, 66.45;
H, 7.04; N, 2.03. IR (Nujol, cm-1): ν(CO) 1925, 1898 (vs), ν-
(Ph, CdC), 1590, 1534 (both w).
C
ipso-Ph, C3a, C8a, C9, C9a), 132.7, 127.1, 125.7 (all s, Ph), 130.9
(s, C5), 127.9 (s, C8), 124.2 (s, C6), 119.2 (s, C3), 118.1 (s, C7),
85.4 (s, Cp), 41.9 (s, C4a), 40.5 (s, C3), 31.1 (s, C4), 28.4 (d, J P-C
) 21.6, PCHCH3), 19.7 and 19.4 (both s, PCHCH3).
31P{1H} NMR (121.4 MHz, 293K, C6D6): δ 63.8 and 63.1-
(both s).
Str u ctu r a l An a lysis of Com p lexes 3, 5, a n d 7a . X-ray
data were collected for all complexes at low temperature on a
Bruker Smart APEX CCD diffractometer at 100.0(2) K equipped
with a normal-focus, 2.4 kW sealed-tube source (molybdenum
radiation, λ ) 0.710 73 Å) operating at 50 kV and 40 mA. Data
were collected over the complete sphere by a combination of
four sets. Each frame exposure time was 10 s covering 0.3° in
ω. Data were corrected for absorption by using a multiscan
method applied with the Sadabs18 program. The structures for
all three compounds were solved by the Patterson method.
Refinement,byfull-matrixleast squares on F2 with SHELXL97,19
was similar for all complexes, including isotropic and subse-
quently anisotropic displacement parameters for all non-
1H and 13C{1H} NMR data for one diastereoisomer: 1H NMR
(300 MHz, 293 K, C6D6) δ 7.16-6.98 (m, 5H, Ph), 6.93 (d, 1H,
J H
1H, J H
) 9.9, H8), 6.71 (s, 1H, H3), 6.07 (m, 1H, H6), 5.97 (dd,
-H
7
8
) 9.9 Hz, J H
) 4.8 Hz, H5), 5.60 (m, 1H, H7),
-H
-H
5
6
4a
5
4.47 (s, 5H, Cp), 4.01 (m, 1H, H4a), 3.17 (s, 3H, CH3), 2.95 (dd,

New N-Heterocyclic Ruthenium Derivatives
Organometallics, Vol. 22, No. 1, 2003 171
hydrogen atoms. The hydrogen atoms were observed or
calculated and refined freely or using a restricted riding model.
All the highest electronic residuals were observed in the close
proximity of the Ru centers and make no chemical sense.
Crystal and data collection and refinement details are given
in Table 4.
00606). M.L.B. thanks the Ministerio de Ciencia y
Tecnolog´ıa (CICYT) of Spain for a Ramon y Cajal
project.
Su p p or tin g In for m a tion Ava ila ble: Tables of atomic
coordinates and equivalent isotropic displacement coefficients,
anisotropic thermal parameters, experimental details of the
X-ray studies, and bond distances and angles for 3, 5, and 7a .
This material is available free of charge via the Internet at
http://pubs.acs.org.
Ack n ow led gm en t. We are grateful for financial
support from the MCYT of Spain (Project BQU 2002-
(18) Blessing, R. H. Acta Crystallogr. 1995, A51, 33-38. SADABS:
Area-Detector Absorption Correction; Bruker-AXS, Madison, WI, 1996.
(19) SHELXTL Package, Version 6.10; Bruker-AXS, Madison, WI,
2000. Sheldrick, G. M. SHELXS-86 and SHELXL-97; University of
Go¨ttingen, Go¨ttingen, Germany, 1997.
OM020652R