Ring-opening isomerization of methylenecyclopropanes catalyzed by hydridorhodium(I) complexes

Article abstract of DOI:10.1016/j.molcata.2005.06.045

2-Phenyl-1-methylenecyclopropane is isomerized into 2-phenyl-1,3-butadiene and 1-phenyl-1,3-butadiene in the presence of catalytic amounts of RhH(CO)(PPh₃)₃ and RhH(PPh₃)₄. The Rh-containing product of the react

Full text of DOI:10.1016/j.molcata.2005.06.045

Journal of Molecular Catalysis A: Chemical 241 (2005) 65–71
Ring-opening isomerization of methylenecyclopropanes
catalyzed by hydridorhodium(I) complexes
Masumi Itazaki, Yasushi Nishihara, Hisami Takimoto,
Chikako Yoda, Kohtaro Osakada∗
Chemical Resources Laboratory (Mail Box R1-03), Tokyo Institute of Technology,
4259 Nagatsuta, Midori-ku, Yokohama 226-8503, Japan
Received 18 March 2005; received in revised form 23 June 2005; accepted 23 June 2005
Available online 10 August 2005
Abstract
2-Phenyl-1-methylenecyclopropane is isomerized into 2-phenyl-1,3-butadiene and 1-phenyl-1,3-butadiene in the presence of catalytic
amounts of RhH(CO)(PPh3)3 and RhH(PPh3)4. The Rh-containing product of the reactions has a 2-phenyl-1-methylallyl (or 1-phenyl-1-
methylallyl) ligand, and is formed also from the reaction of 2-phenyl-1,3-butadiene with RhH(CO)(PPh3)3. RhH(CO)(PPh3)3 promotes
ring-opening isomerization of 4-phenyl-1-methylenespiro[2,2]pentane to afford Rh[η3-anti-CH2C{C( CH2)Ph}CHCH3](PPh3)2 (2) at 50 ◦C
and Rh{κ1,η2-CH2CH(Ph)C( CH2)CH CH2}(CO)(PPh3)2 (3) at −35 ◦C. X-ray crystallography of 2 shows the π-allylic ligand having a
methyl group at anti position. The mechanism for formation of 2 via intermediate 3 is discussed.
© 2005 Elsevier B.V. All rights reserved.
Keywords: Rhodium; C C bond activation; Hydrido complex; Methylenecyclopropane; Diene
1. Introduction
The reaction involves stepwise C C bond cleavage of the
substrate via the metalacyclic intermediates.
Activation of C C bond of organic molecules promoted
by soluble transition metal complexes has attracted signifi-
cant attention in homogeneous catalysis [1,2]. The reactions
do not always take place smoothly because of high stability of
the C C bonds to be cleaved and the occurrence of the metal-
promoted C H bond activation that is kinetically more favor-
able than the C C bond activation. Small-membered ring
molecules often undergo facile C C bond activation accom-
panied by ring opening owing to the release of the ring strain
caused by the reactions [3–6]. Organic compounds having
two small-membered rings with a spiro structure are expected
to exhibit high reactivity toward the reactions involving the
C C bond cleavage. Murakami and Ito reported the selective
conversion of a spiro ketone into the monocyclic substituted
ketone promoted by Rh complexes, as shown in Scheme 1
[7].
Methylenecyclopropanes have high strain energy (ꢀHf
larger than that of cyclopropane by approximately
35 kcal mol−1) [8] and are easily converted into its thermo-
dynamically stable diene isomers in the presence of tran-
sition metal complexes. Recently we reported the reaction
of 2,2-diaryl- and 2,2-dialkyl-1-methylenecyclopropanes
with IrH(CO)(PPh3)3 to afford the Ir complexes having a
2,2-disubstituted 3-butenyl ligand formed via ring open-
ing of the substrate [9,10]. It is closely related to the
ring-opening isomerization of methylenecyclopropanes pro-
moted by the Ir complexes and by the complexes of other
late transition metals. In this paper, we report the reac-
tion of 2-phenyl-1-methylenecyclopropane and 4-phenyl-1-
methylenespiro[2,2]pentane with hydridorhodium(I) com-
plexes to produce the corresponding dienes or the Rh com-
plexes with the ligands formed via ring-opening isomeriza-
tion of the substrate. Results of the reaction of 2-phenyl-1-
methyelenecyclopropane with RhH(CO)(PPh3)3 were partly
reported in a preliminary communication [11].
∗
Corresponding author. Tel.: +81 45 924 5224; fax: +81 45 924 5224.
E-mail address: kosakada@res.titech.ac.jp (K. Osakada).
1381-1169/$ – see front matter © 2005 Elsevier B.V. All rights reserved.
doi:10.1016/j.molcata.2005.06.045

66
M. Itazaki et al. / Journal of Molecular Catalysis A: Chemical 241 (2005) 65–71
(2)
RhH(PPh3)4 also promotes ring-opening isomerization
of 2-phenyl-1-methylenecyclopropane at room tempera-
ture to yield a mixture of 2-phenyl-1,3-butadiene and 1-
phenyl-1,3-butadiene (Eq. (2)). The reaction of 2-phenyl-1-
methylenecyclopropane with IrH(CO)(PPh3)3 was reported
to produce a mixture of the phenyl-1,3-butadienes and the
Ir complex having a 3-butenyl ligand formed via ring open-
ing of 2-phenyl-1-methylenecyclopropane [10,11]. Scheme 2
displays the reaction pathway proposed based on the results
of the reaction of IrH(CO)(PPh3)3. Insertion of a C C bond
of methylenecyclopropane into the Rh H bond produces the
cyclopropylmethylrhodium intermediate. Subsequent C C
bond cleavage of the three-membered ring by ␤-alkyl elimi-
nationleadstotheformationof3-butenylrhodiumcomplexes,
A and B, depending on the C C bond to be cleaved by
the Rh center. ␤-Hydrogen elimination of A and B results
in formation of 2-phenyl-1,3-butadiene and 1-phenyl-1,3-
butadiene, respectively, and regenerates the hydridorhodium
species.
RhH(CO)(PPh3)3-catalyzed reaction of 2-phenyl-1-
methylenecyclopropane produces 2-phenyl-1,3-butadiene
exclusively, suggesting that the C C bond cleavage in (ii)
occurs selectively at the sterically less hindered C C bond.
The diene-forming reaction by RhH(PPh3)4 shows slower
rate and lower selectivity than that by RhH(CO)(PPh3)3.
Slow ␤-hydrogen elimination from the intermediate A
without a CO ligand may result in the decrease in the
Scheme 1.
2. Results and discussion
2.1. Ring-opening isomerization of
2-phenyl-1-methylenecyclopropane by hydridorhodium
complexes
2-Phenyl-1-methylenecyclopropane is isomerized into 2-
phenyl-1,3-butadiene at room temperature in the presence of
the RhH(CO)(PPh3)3 catalyst as shown in Eq. (1). Formation
of1-phenyl-1,3-butedieneisnotobservedduringthereaction.
(1)
Scheme 2.

M. Itazaki et al. / Journal of Molecular Catalysis A: Chemical 241 (2005) 65–71
67
Addition of chloro(methyl)carbene to 2-phenyl-1-
methylenecyclopropane followed by base-promoted
dehydrochlorination of the spiro compound formed affords
the product. The new compound was characterized by
NMR spectroscopy although satisfactory results for ele-
mental analysis were not obtained. 4-Phenyl-1-methyle-
nespiro[2,2]pentane reacts with RhH(CO)(PPh3)3 at 50 ◦C
to produce Rh[η3-anti-CH2C{C( CH2)Ph}CHMe](PPh3)2
(2) in 67% as shown in Eq. (3).
Scheme 3.
total reaction rate and form 1-phenyl-1,3-butadiene via
intermediate B that is in rapid equilibrium with A.
Evaporation of the solvent from the product of reactions
(1) and (2) and removal of the organic compounds by wash-
ing the solid product with solvent yielded the Rh-containing
product which exhibits the 31P{1H} NMR signals as a pair of
doublet of doublets at δ 42.7 and 44.5 due to two magnetically
inequivalent phosphorous nuclei with reasonable coupling
constants (J(P–P) = 24 Hz, J(RhP) = 207 and 196 Hz). Since
the complex does not catalyze the ring-opening isomeriza-
tion in Eqs. (1) and (2), its formation probably deactivates
the catalyst. The reaction of 2-phenyl-1,3-butadiene with
RhH(PPh3)4 also gives the product showing the 31P{1H}
NMR signals at the same positions. These results indicate
that formation of the complex in Eqs. (1) and (2) is ascribed
to the reaction of once formed 2-phenyl-1,3-butadiene with
the hydridorhodium complex in the reaction mixture. The
structure of the complex was tentatively assigned to be
Rh(CH2CPhCHMe)(PPh3)2 (1) based on the NMR data and
the results that the above three reactions produce the common
complex as the major Rh-containing product (Scheme 3).
(3)
Fig. 1 shows molecular structure of 2 determined by X-ray
crystallography. The complex has a 16-electron Rh cen-
ter bonded to the π-allylic ligand and two PPh3 ligands.
˚
Three Rh C bonds of the allylic ligand, 2.144(9)–2.187(9) A,
are similar to the π-allylic rhodium(I) complexes [12–14].
Carbonyl ligand of the starting complex is eliminated dur-
ing the reaction, which is contrasted with the reaction of
1,3-diene and arylallene with RhH(CO)(PPh3)3, giving the
π-allylrhodium complexes with an 18-electron metal cen-
ter, Rh(π-allyl)(CO)(PPh3)2 [15–17]. The methyl group of
the allyl ligand is situated at anti position. Transition metal
π-allylic complexes with the anti substituents were character-
ized by NMR and X-ray crystallography [18–20], although
the number of such complexes was much smaller than the
complexes with syn substituents at the allyl ligand.
1
The H NMR spectrum of 1 shows a signal at δ 1.32
The 31P{1H} NMR spectrum of 2 also contains a pair of
doublet of doublets at δ 41.3 (dd, 1J(P–Rh) = 204 Hz,
2J(P–P) = 22 Hz) and 44.3 (dd, 1J(P–Rh) = 193 Hz,
due to the methyl hydrogens and broad signals at δ 2.53,
3.32 and 3.71, assigned to the hydrogens of the π-allylic
ligand. Another structure of the complex with a 1-phenyl-1-
methylallyl ligand may also be possible, although formation
of the latter complex from 2-phenyl-1,3-butadiene requires
insertion of sterically more hindered C C bond into the
Rh H bond.
2.2. Ring-opening isomerization of
4-phenyl-1-methylenespiro[2,2]pentane
4-Phenyl-1-methylenespiro[2,2]pentane, having two
three-membered rings with a spiro arrangement, is prepared
according to the procedure shown in Scheme 4.
Fig. 1. ORTEP drawing of 2 with 30% thermal ellipsoidal plots. Selected
◦
˚
bond distances (A) and angles ( ): Rh–P1 2.276(2), Rh–P2 2.270(2), Rh–C2
2.185(9), Rh–C3 2.144(9), Rh–C4 2.187(9), C1–C2 1.52(2), C2–C3 1.43(1),
C3–C4 1.42(1), C3–C5 1.50(2), C5–C6 1.33(2), P1–Rh–P2 103.17(9),
C2–Rh–C4 68.4(4), P2–Rh–C4 162.6(3), C2–C3–C4 119.1(9).
Scheme 4.

68
M. Itazaki et al. / Journal of Molecular Catalysis A: Chemical 241 (2005) 65–71
Fig. 2. 1H NMR spectrum of Rh[η3-anti-CH2C{C( CH2)Ph}CHMe]
(PPh3)2 (2) (C6D6, 25 ◦C).
2J(P–P) = 22 Hz). Fig. 2 shows the 1H NMR spectrum
of 2. Signal of methyl hydrogens of the allylic ligand is
observed at δ 1.17. The signals of the other hydrogens of
1
π-allylic ligand are assigned based on the H–1H COSY
spectrum. Sharp signals due to vinylidene hydrogens appear
at reasonable positions, δ 5.09 and 5.53. The hydrogens
bonded to the same allylic carbon are observed at δ 2.43 and
3.21.
Reaction of 4-phenyl-1-methylenespiro[2,2]pentane
with RhH(CO)(PPh3)3 at −35 ◦C produces Rh{κ1,η2-
CH2CHPhC( CH2)CH CH2}(CO)(PPh3)2 (3), as shown
in Eq. (4).
Fig. 3. (a) 1H and (b) 31P{1H} NMR spectra of Rh{κ1,η2-
CH2CH(Ph)C( CH2)CH CH2}(CO)(PPh3)2 (3) formed by the
reaction of 4-phenyl-1-methylenespiro[2,2]pentane with RhH(CO)(PPh3)3
(toluene-d8, −50 ◦C). Small signals in the 1H NMR spectrum may be due
to a minor diastereomer of 3 or organic impurities. Circles and dots in the
31P{1H} NMR spectrum are assigned to major and minor diastereomers of
3, respectively.
at the ␤-carbon. Analogous Rh and Ir complexes having aryl
or alkyl substituents at the ␤-carbon were prepared and fully
characterized in our studies [9–11]. The intermediate com-
plex in this reaction undergoes second ␤-alkyl elimination of
the three-membered ring due to severe ring strain, yielding
complex 3, which is characterized by NMR spectroscopy.
Complex 3 is stable in the solution at low temperature,
although it is not isolated as crystals. Warming the solution
to room temperature leads to formation of π-allylic rhodium
complex 2. β-Hydrogen elimination of the 4-pentenyl ligand
of 3 and reinsertion of the C C double bond of the vinyl
group ( CH CH2) of the triene into the Rh H bond produce
2.
(4)
The complex was not isolated due to facile conversion into
other complexes such as 2 in the solution. Fig. 3 depicts the
1H and 31P{1H} NMR spectra of the complex. The signals
at δ 4.39 and 5.32 are assigned to the vinylidene hydrogens
uncoordinated to the Rh center. The peak positions indicate
that Rh is bonded to the vinyl group ( CH CH2) rather
than the vinylidene group ( C CH2). The vinyl hydrogen
signals are observed at the positions, which are in the mag-
netically higher field than the signals of uncoordinated olefins
(δ 3.35, 2.66, and 1.39). The 31P{1H} NMR spectrum con-
tains the major and minor signals. The complexes can be
assigned to the diastereomers with regard to the configura-
tion of asymmetric carbon of the ligand and face of the vinyl
group coordinated to the Rh center.
This paper presents organic and inorganic products of the
C C bond activation of the strained molecules promoted by
hydridorhodium complexes. The reaction takes place selec-
tively in spite of the high reactivity of the substrate with the
strained structure.
Scheme 5 depicts the plausible pathways for formation of
3 as the initial product of the reaction of the spiro compound
with RhH(CO)(PPh3)3 and its subsequent isomerization into
the final product 2. Insertion of a C C double bond of the
substrate into the Rh H bond and ␤-alkyl elimination of the
resultant cyclopropylmethylrhodium intermediate form the
3-butenylrhodium complex having cyclopropylidene group
3. Experimental
3.1. General
All manipulations of the complexes were carried out
using standard Schlenk techniques under an argon or a

M. Itazaki et al. / Journal of Molecular Catalysis A: Chemical 241 (2005) 65–71
69
Scheme 5.
nitrogen atmosphere. THF and toluene grade were dis-
tilled from sodium and benzophenone prior to use or pur-
chased from Kanto Chemicals Co. Ltd. The starting materials
RhH(PPh3)4 [21,22], RhH(CO)(PPh3)3 [23,24], 2-phenyl-
1-methylenecyclopropane, 1-phenyl-1,3-butadiene, and 2-
phenyl-1,3-butadiene [25,26] were prepared according to
the literature methods. NMR spectra (1H, 13C{1H}, and
31P{1H}) were recorded on JEOL EX-400 or Varian Mer-
cury 300 spectrometers. H3PO4 (85%, δ 0) was used as the
external reference for 31P{1H} NMR. The IR spectra were
recorded on a Shimadzu FTIR-8100A spectrometer in KBr.
Elemental analyses were carried out with a Yanaco MT-5
CHN autocorder.
After the reaction using the RhH(PPh3)4 catalyst, the sol-
vent was removed by evaporation and the resulting solid
was washed with hexane to remove the organic products.
The NMR results shown below suggest the formation of
Rh(η3-CH2CPhCHMe)(PPh3)2 (1). Isolation of the com-
plex was not feasible because it undergoes decomposition
in the solution in the absence of 2-phenyl-1,3-butadiene.
1H NMR (400 MHz, benzene-d6, 25 ◦C): δ 1.32 (dd, 3H,
1
J = 2.6 Hz, J = 4.3 Hz), 2.53 (dd, H, J = 1.6 Hz, J = 6.8 Hz),
3.32 (m, 1H), 3.71 (m, 1H), 6.2–8.1 (m, 35H); 31P{1H} NMR
(160 MHz, benzene-d6, 25 ◦C): δ 42.7 (dd, J(Rh–P) = 207 Hz,
J(P–P) = 24 Hz), 44.5 (dd, J(Rh–P) = 196 Hz, J(P–P) =
24 Hz).
3.2. Reaction of 2-phenyl-1-methylenecyclopropane
with hydridorhodium(I) complexes
3.3. Preparation of
1-chloro-1-methyl-4-phenylspiro[2,2]pentane
To a benzene-d6 (0.6 mL) solution of RhH(CO)(PPh3)3
(27.6 mg, 0.030 mmol) was added 2-phenyl-1-methylene-
cyclopropane (20 mg, 0.15 mmol) at room temperature.
The 1H NMR spectrum after 10 min indicates con-
sumption of 2-phenyl-1-methylenecyclopropane and forma-
tion of 2-phenyl-1,3-butadiene (91% based on 2-phenyl-
1-methylenecyclopropane) without the formation of 1-
phenyl-1,3-butadiene. The major Rh complex in the solu-
tion is RhH(CO)(PPh3)3 at this stage. After 12 h, the
amount of 2-phenyl-1,3-butadiene decreased to 86%. The
reaction using the RhH(PPh3)4 catalyst was carried out
similarly.
To an Et2O (150 mL) solution of 2-phenyl-1-
methylenecyclopropane (7.81 g, 60 mmol) was added
1,1-dichloroethane (25 mL, 300 mmol) at −45 ◦C. After
stirring the solution at that temperature, n-BuLi (1.6 M
hexane solution, 225 mL, 360 mmol) was added dropwise
over 1 h. The solution was gradually warmed to room
temperature and stirred for 30 min at that temperature.
The solution was washed with aqueous NH4Cl and brine
in this order. The organic layer was dried over MgSO4.
Column chromatography (silica gel, hexane, Rf = 0.29)
and bulb-to-bulb distillation (110–120 ◦C / 5 Torr) yielded
1-chloro-1-methyl-4-phenylspiro[2,2]-pentane as colorless

70
M. Itazaki et al. / Journal of Molecular Catalysis A: Chemical 241 (2005) 65–71
oil (9.15 g, 79%). The 1H NMR spectrum indicated the
presence of two diastereomers in 52:48 ratio.
(dd, 1J(P–Rh) = 204 Hz, 2J(P–P) = 22 Hz), 44.3 (dd,
1J(P–Rh) = 193 Hz, 2J(P–P) = 22 Hz).
Analysis calcd. for C12H13Cl:C, 74.80; H, 6.80%. Found:
C, 76.87; H, 7.26%. H NMR (300 MHz, CDCl3, 25 ◦C):
1
3.6. Reaction of 4-phenyl-1-methylenespiro[2,2]pentane
with RhH(CO)(PPh3)3 at low temperature
δ = 1.09 (d, J(H–H) = 5.4 Hz, 1H), 1.18 (t, J(H–H) = 4.8 Hz,
1H), 1.25 (d, J(H–H) = 5.7 Hz, 1H), 1.28 (t, J(H–H) = 4.8 Hz,
1H), 1.35 (d, J(H–H) = 5.7 Hz, 1H), 1.53 (d, J(H–H) = 5.7 Hz,
1H), 1.64 (s, 3H), 1.66 (partially overlapped by methyl pro-
ton, 1H), 1.71 (dd, J(H–H) = 4.8, 8.4 Hz, 1H), 2.43 (dd,
J(H–H) = 4.8, 8.4 Hz, 1H), 2.47 (dd, J(H–H) = 5.4, 8.4 Hz,
1H), 7.06–7.09 (m, 2H), 7.13–7.15 (m, 2H), 7.18–7.22 (m,
2H), 7.25–7.32 (m, 4H). 13C{1H} NMR (75.3 MHz, CDCl3,
25 ◦C): δ = 16.89, 17.61, 21.13, 21.16, 23.08, 23.64, 25.47,
25.62, 30.96, 31.15, 45.15, 45.80, 125.80 (2C), 125.99,
126.39, 128.24, 128.28, 141.04, 141.25.
A toluene-d8 (0.70 mL) solution of RhH(CO)(PPh3)3
(92 mg, 0.10 mmol) in an NMR tube sealed with
a rubber septum was cooled at −78 ◦C. 4-Phenyl-1-
methylenespiro[2,2]pentane (20 ␮L, 0.12 mmol) was added
to the solution through septum. The reaction was monitored
by NMR spectra at −35 ◦C. After 3 h, the 1H, 31P{1H} and
1H–1H COSY spectra of the solution indicated the presence
of Rh{κ1,η2-CH2CH(Ph)C( CH2)CH CH2}(CO)(PPh3)2
1
(3) and its stereoisomer. H NMR (500 MHz, toluene-d8,
−50 ◦C): δ = 1.39 (1H, Hg or Hh), 1.51 (1H, Ha or Hb),
1.75 (1H, Ha or Hb), 2.66 (1H, Hg or Hh), 3.35 (1H,
Hf), 4.39 (1H, He or Hd), 4.46 (1H, Hc), 5.32 (1H, He
or Hd). 31P{1H} NMR (202 MHz, toluene-d8, −20 ◦C):
δ = 29.0 (dd, 1J(P–Rh) = 123 Hz, 2J(P–P) = 19 Hz, minor),
3.4. Preparation of
4-phenyl-1-methylenespiro[2,2]pentane
To a DMSO (150 mL) solution of 1-chloro-1-methyl-
4-phenylspiro[2,2]-pentane (9.15 g, 47.5 mmol) was added
KOtBu (8.1 g, 72 mmol) at room temperature. After stirring
the reaction mixture overnight, the black solution was washed
with aqueous NH4Cl (200 mL), water (500 mL), and brine
(200 mL), in this order, and dried over MgSO4. Purification
by column chromatography (silica gel, hexane, Rf = 0.40) and
bulb-to-bulb distillation (75 ◦C/3 Torr) yielded 4-phenyl-1-
methylenespiro[2,2]pentane as colorless oil (6.3 g, 85%).
Analysis calcd. for C12H12:C, 92.26; H, 7.74%. Found:
1
2
29.2 (dd, J(P–Rh) = 123 Hz, J(P–P) = 19 Hz, major), 31.8
(dd, 1J(P–Rh) = 86 Hz, 2J(P–P) = 19 Hz, minor), 33.5 (dd,
1J(P–Rh) = 86 Hz, 2J(P–P) = 19 Hz, major).
3.7. X-Ray diffraction study
Single crystals of 2 suitable for X-ray diffraction studies
were obtained by recrystallization from hexane at −20 ◦C.
Intensities were collected for Lorentz and polarization effects
on a Rigaku AFC-5R or AFC-7R automated four-cycle
1
C, 90.90; H, 8.31%. H NMR (300 MHz, CDCl3, 25 ◦C):
δ = 1.30 (d, J(HH) = 8.1 Hz, 1H), 1.49 (t, J(H–H) = 4.8 Hz,
1H), 1.54 (d, J(H–H) = 8.1 Hz, 1H), 1.76 (dd, J(H–H) = 4.5,
8.1 Hz, 1H), 2.51 (dd, J(H–H) = 5.4, 8.1 Hz, 1H), 5.25 (t,
J(H–H) = 2.4 Hz, 1H), 5.33 (s, 1H), 7.16–7.23 (m, 3H), 7.32
(m, 2H). 13C{1H} NMR (75.3 MHz, CDCl3, 25 ◦C): δ = 9.02,
19.81, 20.34, 25.94, 98.39, 125.64, 126.14, 128.18, 136.24,
141.27.
˚
diffractiometer by using Mo K␣ radiation λ = 0.7107 A)
and ω–2θ scan method, and an empirical absorption cor-
rection (ψ scan) was applied. Calculations were carried
out by using a program package teXsan for Windows.
The structure was solved by the Patterson method. A
full matrix least-square refinement was used for the non-
hydrogen atoms with anisotropic thermal parameters. All
non-hydrogen atoms were refined with anisotropic thermal
parameters, whereas all hydrogen atoms were located by
assuming the ideal geometry and included in the struc-
ture calculation without further refinement of the param-
eters [27]. Crystal data: orange prisms, C48H43P2Rh, for-
mula weight 784.72, crystal system triclinic, space group
3.5. Reaction of 4-phenyl-1-methylenespiro[2,2]pentane
with RhH(CO)(PPh3)3
To a toluene (4 mL) solution of RhH(CO)(PPh3)3
(230 mg, 0.25 mmol) was added 4-phenyl-1-methyl-
enespiro[2,2]pentane (100 ␮L, 0.60 mmol) at room tem-
perature. Stirring the mixture for 1 h at 50 ◦C caused
change of color from yellow to red. Solvent was removed
under reduced pressure. The resulted dark orange oil
was washed with hexane at −40 ◦C to afford Rh[anti-
η3-CH2C{C( CH2)Ph}CHMe](PPh3)2 (2) as an orange
solid (126 mg, 67%). Analysis calcd. for C48H43P2Rh:C,
73.47; H, 5.52%. Found: C, 73.72; H, 5.80%. 1H NMR
(300 MHz, C6D6, 25 ◦C): δ = 1.17 (m, 3H), 2.43 (d,
J = 6.9 Hz, 1H), 3.21 (m, 1H), 3.29 (m, 1H), 5.09 (d,
J = 1.8 Hz, 1H), 5.53 (d, J = 1.8 Hz, 1H), 6.72–7.94 (m,
35H). 31P{1H} NMR (121.5 MHz, C6D6, 25 ◦C): δ = 41.3
˚
˚
˚
˚
P1 (No. 2), a 12.441(1) A◦, b 18.450(2) A, c 11.608(1) A, α
◦
◦
3
106.275(4) , ␤ 109.448(8) , γ 74.306(2) , V 2365.0(4) A , Z
2, µ 0.455 mm−1, F(0 0 0) 812.00, dcalcd 1.102 g cm−3, crys-
tal size 0.17 mm × 0.15 mm × 0.12 mm, unique reflections
9249, used reflections (F2 > 2.0σ (F2)) 5358, variables 503,
R 0.0710, wR 0.1130, GOF 2.042.
Crystallographic data (excluding structural factors)
have been deposited with the Cambridge Crystallo-
graphic Data Center as supplemental publication no.
CCDC 265899. Copies of this information may be
obtained free of charge from The Director, CCDC,
12 Union Road, Cambridge, CB2 1EZ, UK (fax: +44

M. Itazaki et al. / Journal of Molecular Catalysis A: Chemical 241 (2005) 65–71
71
1223 336 033; e-mail: deposit@ccdc.cam.ac.uk or www:
http://www.ccdc.cam.ac.uk).
[9] M. Itazaki, C. Yoda, Y. Nishihara, K. Osakada, Organometallics 23
(2004) 5402.
[10] M. Itazaki, C. Yoda, Y. Nishihara, K. Osakada, Bull. Chem. Soc.
Jpn 78 (2005) 1469.
[11] Y. Nishihara, C. Yoda, K. Osakada, Organometallics 20 (2001) 2124.
[12] M. McPartlin, R. Mason, J. Chem. Soc. Chem. Commun. (1967) 16.
[13] L.A. Oro, M.T. Pinillos, C. Tejel, C. Foces-Foces, F.H. Cano, J.
Chem. Soc. Dalton Trans. (1986) 2193.
[14] J.H. Bieri, T. Egolf, W. von Philipsborn, U. Piantini, R. Prewo, U.
Ruppli, A. Salzer, Organometallics 5 (1986) 2413.
[15] G. Yagupsky, G. Wilkinson, J. Chem. Soc. A (1969) 725.
[16] K. Osakada, J.-C. Choi, T. Koizumi, I. Yamaguchi, T. Yamamoto,
Organometallics 14 (1995) 4962.
Acknowledgment
This work was partially supported by a Grant-in-aid for
Scientific Research for Young Chemists No. 13740412 from
the Ministry of Education, Culture, Sports, Science and Tech-
nology, Japan.
[17] K. Osakada, M. Kimura, J.-C. Choi, J. Organomet. Chem. 602 (2000)
144.
References
[18] J. Lukas, J.E. Ramakers-Blom, T.G. Hewitt, J.J. Boer, J. Organomet.
Chem. 46 (1972) 167.
[1] B. Rybtchinski, D. Milstein, Angew. Chem. Int. Ed. 38 (1999)
870.
[19] T. Ohta, T. Hosokawa, S. Murahashi, K. Miki, N. Kasai,
Organometallics 4 (1985) 2080.
[2] C.-H. Jun, Chem. Soc. Rev. 33 (2004) 610 (and references cited
therein).
[20] K. Osakada, T. Chiba, Y. Nakamura, T. Yamamoto, A. Yamamoto,
Organometallics 8 (1989) 2602.
[3] R. Noyori, Y. Kumagai, I. Umeda, H. Takaya, H. J. Am. Chem. Soc.
94 (1972) 4018.
[21] K.C. Dewhirst, W. Keim, C.A. Reilly, Inorg. Chem. 7 (1968) 546.
[22] N. Ahmad, J.J. Levison, S.D. Robinson, M.F. Uttley, Inorg. Synth.
28 (1990) 81.
[4] A. Baba, Y. Ohshiro, T. Agawa, J. Organomet. Chem. 110 (1976)
121.
[5] M.A. Huffman, L.S. Liebeskind, J. Am. Chem. Soc. 113 (1991)
2771.
[6] T. Kondo, Y. Kaneko, Y. Taguchi, A. Nakamura, T. Okada, M. Shiot-
suki, Y. Ura, K. Wada, T. Mitsudo, J. Am. Chem. Soc. 124 (2002)
6824.
[7] M. Murakami, K. Takahashi, H. Amii, Y. Ito, J. Am. Chem. Soc.
119 (1997) 9307.
[8] K.B. Wiberg, Angew. Chem., Int. Ed. Engl. 25 (1986) 312.
[23] C. O’Connor, G. Wilkinson, J. Chem. Soc. A (1968) 2665.
[24] N. Ahmad, J.J. Levison, S.D. Robinson, M.F. Uttley, Inorg. Synth.
15 (1974) 45.
[25] B.A. Patel, J.E. Dickerson, R.F. Heck, J. Org. Chem. 43 (1978) 5018.
[26] S. Nunomoto, Y. Kawakami, Y. Yamashita, Bull. Chem. Soc. Jpn.
54 (1981) 2831.
[27] International Tables for X-ray Crystallography, vol. 4, Kynoch, Birm-
ingham, England, 1974.