Nucleophilic attack in methoxycarbenes: Heterolytic cleavage of the carbon (sp3)-oxygen bond versus aminolysis

Article abstract of DOI:10.1021/om400565c

The iridium methoxycarbene [IrCp*Cl{=C(OMe)CH=CPh₂} (PPh₂Me)]PF₆ (3) can undergo a clean attack by nucleophiles at least by two different pathways: (1) an unusual nucleophilic attack of primary, secondary, and tertiary amines at the sp³ carbon-oxygen bond, which gives an acyl complex and amine alkylation and (2) a nucleophilic attack of the ammonia at the carbenic carbon, which forms a primary aminocarbene.

Full text of DOI:10.1021/om400565c

Article
pubs.acs.org/Organometallics
Nucleophilic Attack in Methoxycarbenes: Heterolytic Cleavage of the
Carbon (sp3)−Oxygen Bond versus Aminolysis
†
,†
†
†
†
‡
́
M. Talavera, S. Bolano,* J. Bravo, J. Castro, S. Garcıa-Fontan, and J. M. Hermida-Ramon
́
́
̃
†
‡
́
́
́
Departamento de Quımica Inorganica and Departamento de Quımica Fısica, Universidad de Vigo, Campus Universitario, E-36310
́
Vigo, Spain
S
* Supporting Information
ABSTRACT: The iridium methoxycarbene [IrCp*Cl{C(OMe)-
CHCPh2}(PPh2Me)]PF6 (3) can undergo a clean attack by
nucleophiles at least by two different pathways: (1) an unusual
nucleophilic attack of primary, secondary, and tertiary amines at the sp3
carbon−oxygen bond, which gives an acyl complex and amine
alkylation and (2) a nucleophilic attack of the ammonia at the carbenic
carbon, which forms a primary aminocarbene.
INTRODUCTION
RESULTS AND DISCUSSION
■
■
The reactivity of alkoxycarbenes is well known,1 especially with
metals of groups 6−8. Alkoxycarbene complexes undergo a
nucleophilic attack at the carbene carbon2 to form other
carbene complexes. A well-known example of this behavior is
aminolysis of alkoxycarbenes by amines.2,3 This reaction can be
envisioned as a Lewis acid−base reaction, in which the carbene
carbon atom is the Lewis acid, the electron-pair acceptor, and
the amine is the Lewis base, the electron-pair donor. In this
process, primary or secondary amines attack the carbenic
carbon and the proton of the amine leads to the displacement
of the alkoxy group as an alcohol. Another example of
nucleophilic attack in alkoxycarbene complexes is the
heterolytic cleavage of the carbon (sp3)−oxygen bond. Thus,
this occurs when the nucleophiles are metal carbonyl anions,4
when the nucleophiles are strong (for example I−),5 or when
the cationic alkoxycarbene complex has π-acceptor ligands in
the first coordination sphere (for example, CO and P-
(OMe)3).5a,6 However, to the best of our knowledge there
are only two examples where heterolytic cleavage appears with
amines, and so far there is not a clear explanation for this
reactivity.7 It may be due to electronic or to steric hindrance
reasons, which favor the heterolytic cleavage of the carbon
(sp3)−oxygen bond above the acid−base reaction. The aim of
this work is to show that the heterolytic cleavage reaction plays
a relevant role in the reactivity of alkoxycarbenes. In order to do
that, we present (i) the synthesis of an iridium methoxycarbene
complex by nucleophilic attack of methanol at an iridium
allenylidene complex and (ii) the reactivity of the iridium
methoxycarbene complex with different amines and aqueous
ammonia solution.
Synthesis and Reactivity with Strong Bases of a
(Methoxyalkenylcarbene)iridium Complex. The reaction
of the half-sandwich (acetonitrile)iridium(III) complex
[IrCp*Cl(NCMe)(PPh2Me)]PF6 (2) (which was obtained by
reacting the complex [IrCp*Cl2(PPh2Me)] (1)8 with TlPF6 in
acetonitrile; see the Experimental Section) with 1,1-diphenyl-2-
propyn-1-ol in methanol gave a yellow solution which
immediately turned purple, and finally an orange solid was
obtained, [IrCp*Cl{C(OMe)CHCPh2}(PPh2Me)]PF6
(3) (Scheme 1). Complex 3 was isolated in 80% yield. The
NMR spectra supported the proposed formulation, which was
further confirmed by an X-ray crystal structure determination of
complex 3 (Figure 1). For the carbene ligand (IrC(OCH3)-
CHCPh2) of 3, the 13C{1H} NMR spectrum exhibits a
characteristic low-field resonance at δ 263.3 (s br) ppm for the
α-carbon and resonances at 148.6 (s) and 136.6 (s) ppm for the
γ- and β-carbons, respectively. The signal corresponding to Cβ-
1
H in the H NMR spectrum appears as a broad singlet at 5.37
ppm.
The formation of 3 may be explained according to the initial
formation of an allenylidene complex as an intermediate (A).
After that, nucleophilic attack by the oxygen atom of methanol
on the Cα of the allenylidene followed by proton transfer at Cβ
gives the final (methoxyalkenylcarbene)iridium complex 3
(Scheme 1). Nucleophilic attack by alcohols on the Cα atom
of the allenylidene ligand has previously been reported for
other metal complexes9 but not for iridium complexes,
c o m p o u n d
3 b e i n g t h e fi r s t h a l f - s a n d w i c h
Received: June 17, 2013
© XXXX American Chemical Society
A
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ligand (Cp*) η5-coordinated to an iridium atom, which is also
coordinated to other three donor atoms, leading to the
formation of a “three-legged piano stool” structure with
pseudooctahedral geometry. These ligands are a Fisher-type
carbene ligand (1-methoxy-3,3-diphenylprop-2-en-1-ylidene), a
chlorine ligand, and a diphenylmethylphosphane ligand. The
carbene Ir−C bond length in complex 3 and in the complex
[IrCp*{C(OMe)CH2Ph}{PPh2(C6H3-2-(OMe)-6-
O)}]PF611 has the same value, 1.973(5) Å. This bond length is
shorter than the Ir−C σ-bond length for other complexes,11
showing the presence of some multiple-bond character in the
Ir−C carbene bond. However, this value is slightly longer than
that found in the Fischer-type iridium carbenes of formula Ir
C(H)OR.12
Scheme 1. Formation of Allenylidene (A),
Methoxyalkenylcarbene (3), and Methoxyallenyl (4)
Complexes of Iridium
The complex 3 can be deprotonated with a strong base. The
addition of 5 equiv of KOtBu to a dichloromethane solution of
3 leads to the neutral methoxyallenyl derivative [IrCp*Cl{C-
(OMe)CCPh2}(PPh2Me)] (4) as a result of the
abstraction of the hydrogen atom bonded to the β-carbon of
3, which is isolated as a brown solid in 60% yield. This reaction
is reversible, and complex 3 can be regenerated by addition of 1
equiv of HBF4·Et2O to a dichloromethane solution of 4
(Scheme 1).
(methoxyalkenylcarbene)iridium complex known. In order to
confirm our hypothesis about the mechanism of the reaction,
the compound 2 was treated with an excess of 1,1-diphenyl-2-
propyn-1-ol in dichloromethane-d2, which gave a purple
solution due to the formation of [IrCp*Cl(CCCPh2)-
(PPh2Me)]PF6 (A). Complex 3 was obtained when methanol
was added to this solution, which confirmed our hypothesis.
Compound A is the first half-sandwich iridium allenylidene
complex known, but unfortunately this product began to
decompose at the same time it was formed.10 We were able to
fully characterize the intermediate A at low temperature (243
K) by multinuclear (1H, 31P{1H}, 13C{1H}) and multidimen-
sional ({1H,1H} COSY, {1H, 13C} HSQC, and {1H, 13C}
HMBC) NMR experiments and, in the solid state, by IR.
Confirmatory evidence of the presence of the allenylidene
moiety comes from both the IR spectrum (νCCC) weak band
at 1989 cm−1) and the 13C{1H} spectrum with resonances at
238.7 (d, 2JC−P = 16.3 Hz, Cα), 175.3 (s, Cγ), and 169.4 (s, Cβ)
ppm.
In the 1H NMR spectrum of 4 the most noticeable feature is
the absence of the CHCPh2 resonance. In the 13C{1H} NMR
spectrum the resonance of the α-carbon atom of the allenyl
ligand is observed as a doublet at 123.0 ppm with a C−P
coupling constant of 17.7 Hz; the β- and γ-carbon resonances
are observed as singlets at 197.0 and 112.5 ppm, respectively.
The IR spectrum shows a weak band at 1889 cm−1 due to the
νCCC band of the allenyl ligand.
Heterolytic Cleavage of the Carbon (sp3)−Oxygen
Bond of the (Methoxyalkenylcarbene)iridium Complex
by Amines. The analogue of a metal alkoxycarbene complex in
organic chemistry is an ester. This analogy is very useful to
explain the development of metal alkoxycarbene reactions. For
example, the reaction of an ester with primary or secondary
amines results in an amide, which is an aminolysis reaction. The
same reaction appears in organometallic chemistry.3 It is usually
assumed that the reaction of a primary or a secondary amine
with an alkoxycarbene is through attack at the carbene carbon,
producing an aminocarbene (Scheme 2).
The ORTEP representation of 3 is given in Figure 1 with the
ellipsoids drawn at a probability level of 50%, while selected
bond and angle parameters for 3 are given in Table 1. The
complex cation 3 is formed by a pentamethylcyclopentadienyl
Unexpectedly, when a dichloromethane solution of the
methoxycarbene compound 3 was reacted with a wide variety
of amines (MeNH2, EtNH2, Et2NH, PrNH2, Pr2NH, PhNH2,
CyNH2, Cy2NH, piperidine, NEt3), we observed in all cases the
formation of the acyl complex [IrCp*Cl{C(O)CHCPh2}-
(PPh2Me)] (5). As is well known, the Fischer-type carbenes
react with water to give hydroxycarbenes by nucleophilic
substitution of the alkoxy group (eliminated as alcohol)13 and
the hydroxycarbenes (generally unstable) may degrade to give
acyl derivatives.13c,14 To rule out this possibility, we treated
compound 3 with water, but compound 3 remained stable and
we did not detect the formation of the acyl derivative.
Therefore, 5 is a consequence of the attack of the amine at
the carbon (sp3)−oxygen bond (Scheme 3).
Additionally, we have observed that the formation of
acyliridium complex 5 comes always with a mixture of
ammonium salts with different degrees of methylation. This
finding indicates that the methoxycarbene 3 behaves as a
methylating agent of amines, in a way similar to that for well-
known methyl halides reacting with nitrogen nucleophiles in an
organic reaction15 (Scheme 4). Another finding supporting this
Figure 1. Cationic complex [IrCp*Cl{C(OMe)CHCPh2}-
(PPh2Me)]+ (3).
B
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Table 1. Selected Bond Lengths (Å) and Angles (deg) for 3
a
Ir−CT01
Ir−P(1)
Ir−C(1)
Ir−C(3)
1.8835(2)
2.3063(12)
2.247(5)
2.264(5)
2.239(5)
1.355(6)
1.317(6)
128.18(14)
125.24(3)
92.45(4)
130.8(4)
115.8(3)
Ir−C(12)
Ir−Cl
Ir−C(2)
Ir−C(4)
C(11)−C(12)
O(1)−C(13)
1.973(5)
2.4147(12)
2.190(5)
2.250(5)
1.464(7)
1.471(6)
Ir−C(5)
C(11)−C(14)
O(1)−C(12)
CT01−Ir−C(12)
CT01−Ir−P(1)
P(1)−Ir−Cl
C(14)−C(11)−C(12)
O(1)−C(12)−Ir
CT01−Ir−Cl
C(12)−Ir−P(1)
C(12)−Ir−Cl
O(1)−C(12)−C(11)
C(11)−C(12)−Ir
120.73(3)
89.93(14)
89.87(14)
120.7(4)
123.5(3)
a
CT01 refers to the centroid of the Cp* ligand.
of the Cl− ligand (eq 1). Similar reactions can be found in the
literature.13c,14b
Scheme 2. Reaction of Aminolysis of a Metal Alkoxycarbene
Scheme 3. Reaction of Heterolytic Cleavage of the Carbon
(sp3)−Oxygen Bond by Amines
The presence of a terminal carbonyl ligand in complex 6 is
confirmed by a strong IR band at 2035 cm−1 for νCO, as well as
by a doublet signal at δ 165.3 ppm with a C−P coupling
constant of 13.7 Hz in the 13C{1H} NMR spectrum. In
addition, a doublet at 115.1 ppm with a C−P coupling constant
of 13.9 Hz and a broad singlet at 152.1 ppm can be assigned to
Scheme 4. Methylation of Amines by Metal Methoxycarbene
1
the Cα and Cβ nuclei of the vinyl ligand, respectively. The H
NMR spectrum of 6 shows a doublet at 7.0 ppm with a C−P
coupling constant of 8.8 Hz, which corresponds to the
hydrogen on the α-carbon of the vinyl ligand. All resonance
assignments were confirmed by {1H,13C} HSQC and {1H,13C}
HMBC experiments.
The structure of the cation complex 6 consists of a
pentamethylcyclopentadienyl ligand (Cp*) η5-coordinated to
an iridium atom, which is also coordinated to three donor
atoms, leading to the formation of a “three-legged piano stool”
structure with pseudooctahedral geometry. These ligands are a
2,2-diphenylethenyl ligand, a carbonyl ligand, and a diphenyl-
methylphosphane ligand. The ORTEP representation of 6 is
given in Figure 2 with the ellipsoids drawn at a probability level
of 30%, while selected bond and angle parameters for 6 are
given in Table 2.
When 1.1 equiv of a strong acid (HBF4·Et2O or HOSO2CF3)
was added to 5 in a solution of dichloromethane, the
hydroxycarbene [IrCp*Cl{C(OH)CHCPh2}PPh2Me]X
(7; X = BF4, OSO2CF3) was isolated as a red solid in 87%
yield. This reaction is reversible by addition of Et3N (Scheme
5).
The hydroxycarbene 7 was unambiguously characterized by
NMR spectroscopy ({1H,13C} HMBC, {1H,13C} HSQC, 13C-
{1H}) and confirmed by refluxing complex 2 with water and
1,1-diphenyl-2-propyn-1-ol for 30 min.16 When the reaction
mixture of 5 and trifluoromethanesulfonic acid was set aside for
2 h, the carbonyl complex 817 and 1,1-diphenylethene18 were
formed. Moreover, when the same reaction was performed with
4 equiv of acid and set aside overnight, the 1,1-diphenylethene
proposal occurs when the reaction is carried out with the
tertiary amine Et3N; in this case only the ammonium salt
[Et3MeN]PF6 accompanies the formation of complex 5.
The spectral data confirmed the formulation of 5 as
[IrCp*Cl{C(O)CHCPh2}(PPh2Me)]. The most notewor-
thy facts in these data are the disappearance of the OCH3 and
Cβ-H signals in the 1H NMR experiment and the presence of a
new signal at 7.7 ppm corresponding to CHCPh2. Moreover, a
signal in the 13C{1H} NMR experiment appearing at 219.0 ppm
as a doublet with a C−P coupling constant of 13.0 Hz
corresponds to η1-C(O)CHCPh2. All of this confirms the
presence of the acyl ligand, η1-C(O)CHCPh2. The IR spectrum
of complex 5 shows a band at 1577 cm−1 due to the νCO band
of the acyl ligand. Compound 5 is thermodynamically unstable
in methanol solution at room temperature and spontaneously
converts to [IrCp*(CHCPh2)(CO)(PPh2Me)]Cl (6·Cl) by
CO deinsertion of the acyl ligand and concurrent displacement
C
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Scheme 5. Formation of Hydroxycarbene and Its Evolution
to 1,1-Diphenylethene and 3-Methyl-1,1,3-triphenylindane
Scheme 6. Formation of 3-Methyl-1,1,3-triphenylindane by
Diphenylethene in Acid Media
Figure 2. Cationic complex [IrCp*(CHCPh2)(CO)(PPh2Me)]+
(6).
transformed into 3-methyl-1,1,3-triphenylindane.19 A plausible
mechanism (Scheme 6) may involve the reaction of 1,1-
diphenylethene with excess acid. A similar reaction was found
in the literature,20 but the mechanism was not reported.
Aminolysis via Aqueous Ammonia Solution. Surpris-
ingly, and in contrast to what was observed with amines, when
an aqueous ammonia solution (30%) was added to a
dichloromethane solution of 3 a typical aminolysis reaction
occurred and the primary aminocarbene [IrCp*Cl{C(NH2)-
CHCPh2}PPh2Me]PF6 (9) was obtained as an orange solid
in 82% yield (eq 2).
9 were unambiguously assigned by means of {1H,13C} HSQC,
{1H,13C} HMBC, and {1H,1H} COSY experiments.
CONCLUSION
■
In this paper we have reported the formation of the first half-
sandwich allenylidene complex of iridium by a Selegue reaction
and the first (methoxyalkenylcarbene)iridium complex via an
allenylidene complex. In addition, we have studied the behavior
of this iridium carbene complex with amines and have observed
an unusual nucleophilic attack of the amine at the carbon
(sp3)−oxygen bond, which gives an acyl complex and amine
alkylation. In contrast, ammonia forms a primary aminocarbene
by a typical aminolysis reaction.
Experimental results suggest that a competitive process
occurs between aminolysis and heterolytic cleavage of the
carbon (sp3)−oxygen bond. This process is likely due to a steric
effect and not a nucleophilic effect, because the nucleophilicity
1
The H NMR spectrum of 9 shows a singlet at 6.8 ppm for
Cβ-H and two broad singlets at 8.3 and 9.7 ppm corresponding
to the NH2 group.21 Its 13C{1H} NMR spectrum confirms the
presence of a carbene ligand. The carbene carbon appears as a
doublet with a chemical shift of 209.9 ppm and a C−P coupling
constant of 11.9 Hz. All of the proton and carbon resonances of
Table 2. Selected Bond Lengths (Å) and Angles (deg) for 6
a
Ir−C(0)
Ir−C(11)
Ir−C(1)
Ir−C(3)
1.869(3)
2.072(3)
2.266(3)
2.259(3)
2.277(3)
1.342(4)
1.498(4)
Ir−CT01
Ir−P(1)
Ir−C(2)
1.90114(14)
2.3022(8)
2.255(3)
2.234(3)
1.144(4)
1.494(4)
Ir−C(4)
Ir−C(5)
C(0)−O(0)
C(12)−C(21)
C(11)−C(12)
C(12)−C(31)
C(11)−Ir−P(1)
C(0)−Ir−C(11)
CT01−Ir−C(11)
O(0)−C(0)−Ir
C(11)−C(12)−C(21)
C(21)−C(12)−C(31)
83.64(8)
C(0)−Ir−P(1)
C(0)−Ir−CT01
CT01−Ir−P(1)
C(12)−C(11)−Ir
C(11)−C(12)−C(31)
91.61(10)
125.36(9)
129.01(2)
132.8(2)
98.14(12)
118.48(8)
171.1(3)
119.4(3)
117.7(3)
122.8(3)
a
CT01 refers to the centroid of the Cp* ligand.
D
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of ammonia is intermediate among the other amines used in
this work.
Table 3. Crystal Data and Structure Refinement Details for
Complexes 3 and 6
3
6
EXPERIMENTAL SECTION
■
empirical formula
formula wt
temp (K)
wavelength (Å)
cryst syst
space group
a (Å)
C39H42ClF6IrOP2
930.32
C62H59BIrOP
1054.07
General Procedures, Methods, and Materials. All experiments
were carried out under an atmosphere of argon by Schlenk techniques.
Solvents were dried by the usual procedures22 and, prior to use,
distilled under argon. The starting material [IrCp*Cl2(PPh2Me)] (1)
was prepared as described in the literature.8 All reagents were obtained
from commercial sources. Unless stated, NMR spectra were recorded
at room temperature on a Bruker ARX-400 instrument, with
resonating frequencies of 400 MHz (1H), 161 MHz (31P{1H}), 376
MHz (19F{1H}), and 100 MHz (13C{1H}) using the solvent as the
183(2)
173(2)
0.71073
triclinic
P1
monoclinic
C2/c
̅
40.922(3)
12.8637(10)
14.6334(12)
90
11.9619(8)
12.5140(8)
18.5316(12)
73.8360(10)
87.8390(10)
72.0190(10)
2530.7(3)
2
b (Å)
c (Å)
1
internal lock. H and 13C{1H} signals are referred to internal TMS,
α (deg)
those of 19F{1H} to CFCl3, and those of 31P{1H} to 85% H3PO4;
β (deg)
101.3580(10)
90
1
downfield shifts (expressed in ppm) are considered positive. H and
γ (deg)
V (Å3)
13C{1H} NMR (or JMOD) signal assignments were confirmed by
7552.2(10)
8
{1H,1H} COSY, {1H,13C} HSQC, {1H,13C} HMBC, and DEPT
experiments. Coupling constants are given in hertz. Infrared spectra
were run on a Jasco FT/IR-6100 spectrometer using KBr pellets. C, H,
and N analyses were carried out with a Carlo Erba 1108 analyzer.
High-resolution electrospray mass spectra were acquired using an
apex-Qe spectrometer.
Z
density (Mg/m3)
1.636
1.383
abs coeff (mm−1
)
3.751
2.711
F(000)
3696
1072
cryst size (mm)
0.48 × 0.37 × 0.05
θ range for data collection 1.66−28.03
0.43 × 0.31 × 0.29
1.79_28.01
X-ray Diffraction Analysis. Crystallographic data were collected
on a Bruker Smart 1000 CCD diffractometer at CACTI (Universidade
de Vigo) using graphite-monochromated Mo Kα radiation (λ =
0.71073 Å) and were corrected for Lorentz and polarization effects.
The software SMART23 was used for collecting frames of data and
indexing reflections and the determination of lattice parameters,
SAINT24 for integration of intensity of reflections and scaling, and
SADABS25 for empirical absorption correction.
(deg)
index ranges
−53 ≤ h ≤ 52
−15 ≤ k ≤ 16
−19 ≤ l ≤ 18
24349
−15 ≤ h ≤ 14
−12 ≤ k ≤ 16
−23 ≤ l ≤ 24
17026
no. of rflns collected
no. of indep rflns
8969 (R(int) =
11736 (R(int) =
0.0456)
0.0247)
The crystallographic treatment of the compounds was performed
with the Oscail program.26 The structure was solved by direct methods
and refined by full-matrix least squares based on F2.27 All non-
hydrogen atoms were refined with anisotropic displacement
parameters. Hydrogen atoms were included in idealized positions
and refined with isotropic displacement parameters.
no. of rflns obsd (>2σ)
data completeness
abs cor
6308
10081
0.959
0.979
semiempirical from equivalents
max and min transmission 0.7456 and 0.4464
0.7456 and 0.6256
full-matrix least squares on F2
refinement method
no. of data/restraints/
params
goodness of fit on F2
8969/0/460
11736/0/601
Crystal data and structure refinement details for complexes 3 and 6
are given in Table 3.
1.044
1.003
Synthesis and Characterization of New Complexes. Prep-
aration of [IrCp*Cl(NCMe)(PPh2Me)]PF6 (2). An orange solution of
[IrCp*Cl2(PPh2Me)] (500 mg, 0.83 mmol) in acetonitrile (25 mL)
was treated with thallium(I) hexafluorophosphate (385.6 mg, 1.105
mmol). The reaction mixture was stirred for 50 min at room
temperature and then was filtered through Celite to give a yellow
solution. The solvent was removed by vacuum, and the solid obtained
was redissolved in dichloromethane. The solution was filtered through
Celite again, and the solvent was removed by vacuum to yield a yellow
solid that was washed with diethyl ether (3 × 2 mL). Finally it was
R indices (I > 2σ(I))
R1 = 0.0348, wR2 =
0.0727
R1 = 0.0294, wR2 =
0.0600
R indices (all data)
R1 = 0.0703, wR2 =
0.0883
R1 = 0.0401, wR2 =
0.0647
largest diff peak and hole
1.619 and −0.979
1.098 and −0.735
(e Å−3
)
243 K): δ 238.7 (d, 2JC−P = 16.3 Hz, Cα); 175.3 (s, Cγ); 169.4 (s, Cβ);
2
124.7−135.6 (C Ph); 103.9 (d, JC−P = 2.0 Hz, C5(CH3)5); 15.7 (d,
1
1JC−P = 42.0 Hz, PPh2CH3); 8.7 (s, C5(CH3)5) ppm. IR (cm−1):
νCCC 1989 (w).
dried under vacuum. Yield: 600 mg (96%). H NMR (CD2Cl2): δ
7.45−7.70 (m, 10H, PPh2CH3); 2.39 (s br, 3H, NCCH3); 2.31 (d, 3H,
2JH−P = 10.8 Hz, PPh2CH3); 1.54 (d, 15H, 4JH−P = 2.4 Hz, C5(CH3)5)
ppm. 31P{1H} NMR (CD2Cl2): δ −9.75 (s, PPh2CH3); −144.10 (sept,
1JP−F = 710.8 Hz, PF6) ppm. 13C{1H} NMR (CD2Cl2): δ 128.6−133.9
(C PPh2Me); 121.2 (s, NCCH3); 95.4 (d, 2JC−P = 2.4, C5(CH3)5); 13.2
Preparation of [IrCp*Cl{C(OMe)CHCPh2}(PPh2Me)]PF6 (3).
When 1,1-diphenyl-2-propyn-1-ol (93 mg, 0.44 mmol) was added to a
yellow solution of 2 (294 mg, 0.39 mmol) in methanol (10 mL), the
mixture immediately turned purple. After 20 min of stirring an orange
suspension was obtained. This suspension was concentrated to ca. 4
mL, yielding an orange solid that was separated by decantation,
washed with pentane (5 × 8 mL), and dried under vacuum.
Recrystallization of this complex from a CH2Cl2/MeOH mixture (1/
1 v/v) yielded red monocrystals adequate for X-ray diffraction analysis.
Yield: 292 mg (80%). 1H NMR (CD2Cl2): δ 7.54−7.67 (m, 6H,
PPh2CH3); 7.45−7.54 (m, 5H, CPh2 + PPh2CH3); 7.35−7.44 (m, 3H,
CPh2); 7.21−7.29 (m, 2H, CPh2); 6.93−7.00 (m, 2H, CPh2); 6.68−
6.76 (m, 2H, CPh2); 5.37 (s, 1H, Cβ-H); 3.91 (s br, 3H, OCH3); 2.41
1
(d, JC−P = 40.8 Hz, PPh2CH3); 8.7 (s, C5(CH3)5); 4.0 (s, NCCH3)
ppm. IR (cm−1): νCN 2324 (w), 2296 (w); νPF 841 (s).
6
In Situ NMR Formation of [IrCp*Cl(CCCPh2)(PPh2Me)]PF6
(A). A yellow solution of 2 (31.1 mg, 0.042 mmol) in dichloro-
methane-d2 (600 μL) was placed in an NMR tube, and a solution of
1,1-diphenyl-2-propyn-1-ol (34.6 mg, 0.168 mmol) in dichloro-
methane-d2 (50 μL) was added through the serum cap via a
microsyringe at 243 K; immediately a change in color to purple was
observed. Once the NMR study was completed, the solvent was
removed and the residue was used to prepare the KBr pellet to record
2
4
(d, 3H, JH−P = 10.5 Hz, PPh2CH3); 1.53 (d, 15H, JH−P = 2.0 Hz,
C5(CH3)5) ppm. 31P{1H} NMR (CD2Cl2): δ −14.97 (s, PPh2CH3);
−144.11 (sept, 1JP−F = 710.6 Hz, PF6) ppm. 13C{1H} NMR (CD2Cl2):
δ 263.3 (s br, Cα); 148.6 (s, Cγ); 139.8 (s, Cipso-Ph); 139.5 (s, Cipso-Ph);
136.6 (s, Cβ-H); 133.3 (d, 2JC−P = 9.4 Hz, C PPh2Me); 132.8 (d, 2JC−P
1
the IR spectrum. H NMR (CD2Cl2, 243 K): δ 7.22−7.97 (m, Ph);
2
2.29 (d, 3H, JH−P = 11.5 Hz, PPh2CH3); 1.63 (s, 15H, C5(CH3)5)
ppm. 31P{1H} NMR (CD2Cl2, 243 K): δ −3.93 (s, PPh2CH3);
1
−144.27 (sept, JP−F = 711.5 Hz, PF6) ppm. 13C{1H} NMR (CD2Cl2,
E
dx.doi.org/10.1021/om400565c | Organometallics XXXX, XXX, XXX−XXX

Organometallics
Article
= 9.4 Hz, C PPh2Me); 132.3 (d, 3JC−P = 2.8 Hz, C PPh2Me); 132.2 (d,
3JC−P = 2.8 Hz, C PPh2Me); 131.1 (d, 1JC−P = 32.6 Hz, P-Cipso); 130.8
(s, 1C CPh2); 130.6 (s, 1C CPh2); 130.5 (d, 1JC−P = 31.9 Hz, P-Cipso);
129.6 (s, 1C CPh2); 129.5 (s, 1C CPh2); 129.5 (s, 2C CPh2); 129.5 (s,
1C CPh2); 129.4 (s, C PPh2Me); 129.4 (s, C PPh2Me); 129.4 (s, 1C
CPh2); 128.8 (s, 2C CPh2); 101.2 (d, 2JC−P = 1.9 Hz, C5(CH3)5); 69.6
Cl]+. Anal. Calcd for C38H39OClIrP (770.37): C, 59.25; H, 5.10.
Found: C, 59.44; H, 5.20.
Preparation of [IrCp*(CHCPh2)(CO)(PPh2Me)]Cl (6). An orange
solution of 5 (100 mg, 0.13 mmol) in methanol (5 mL) was stirred for
24 h. Then, the solvent was removed by vacuum, yielding a white
precipitate which was washed with pentane (3 × 3 mL) and finally
dried under vacuum. Yield: 97 mg (85%). Treating complex 6 with
NaPF6 or NaBPh4 in methanol produced the corresponding anion
1
3
(s, OCH3); 13.6 (d, JC−P = 43.2 Hz, PPh2CH3); 8.9 (d, JC−P = 0.9
Hz, C5(CH3)5) ppm. IR (cm−1): νPF 845 (s). MS (m/z, referred to the
6
−
interchange. In the case of BPh4 monocrystals of [IrCp*(CH
most abundant isotopes): 785 [M]+. Anal. Calcd for C39H42OClF6IrP2
(930.37): C, 50.35; H, 4.55. Found: C, 50.43; H, 4.59.
CPh2)(CO)(PPh2Me)]BPh4 adequate for X-ray diffraction analysis
were obtained. The PF6− derivative was employed for characterization.
Preparation of [IrCp*Cl{C(OMe)CCPh2}(PPh2Me)] (4). KtBuO
(63 mg, 0.54 mmol) was added to an orange solution of 3 (100 mg,
0.11 mmol) in dichloromethane (15 mL). The reaction mixture was
stirred for 30 min at room temperature, and then it was filtered
through Celite. The solvent of the brown filtrate was removed by
vacuum, giving an oil, which was treated with diethyl ether. The brown
solid that formed was separated by decantation, washed with diethyl
1
Data for [IrCp*(CHCPh2)(CO)(PPh2Me)]PF6 are as follows. H
NMR (CD2Cl2): δ 7.62−7.73 (m, 3H, PPh2CH3); 7.42−7.58 (m, 5H,
PPh2CH3); 7.18−7.32 (m, 8H, CPh2 + PPh2CH3); 7.09−7.14 (m, 2H,
3
CPh2); 7.02 (d, 1H, JH−P = 8.8 Hz, CHCPh2); 6.55−6.61 (m, 2H,
CPh2); 2.33 (d, 3H, 2JH−P = 10.5 Hz, PPh2CH3); 1.83 (d, 15H, 4JH−P
=
2.3 Hz, C5(CH3)5) ppm. 31P{1H} NMR (CD2Cl2): δ −13.84 (s,
1
PPh2CH3); −143.94 (sept, JP−F = 710.4 Hz, PF6) ppm. 13C{1H}
1
2
ether (3 × 2 mL), and dried under vacuum. Yield: 51 mg (60%). H
NMR (CD2Cl2): δ 165.3 (d, JC−P = 13.7 Hz, CO); 152.1 (s, CH
CPh2); 146.0 (s, Ph-Cipso); 144.3 (s, Ph-Cipso); 133.4 (d, 3JC−P = 2.8 Hz,
NMR (CD2Cl2): δ 6.94−7.81 (m, 20H, Ph); 3.59 (s br, 3H, OCH3);
2.18 (d, 3H, 2JH−P = 9.8 Hz, PPh2CH3); 1.38 (d, 15H, 4JH−P = 2.1 Hz,
C5(CH3)5) ppm. 31P{1H} NMR (CD2Cl2): δ −8.88 (s, PPh2CH3)
ppm. 13C{1H} NMR (CD2Cl2): δ 197.0 (s, Cβ); 142.6 (s, Cipso-Ph);
3
2
C PPh2Me); 132.7 (d, JC−P = 2.8 Hz, C PPh2Me); 132.4 (d, JC−P
=
10.0 Hz, C PPh2Me); 132.2 (d, 2JC−P = 10.0 Hz, C PPh2Me); 130.1 (s,
C CPh2); 130.0 (d, 2JC−P = 11.3 Hz, C PPh2Me); 129.5 (d, 2JC−P = 11.4
Hz, C PPh2Me); 128.9 (s, C CPh2); 128.7 (s, C CPh2); 128.1 (s, C
CPh2); 127.8 (s, P-Cipso); 127.2 (s, C CPh2); 127.1 (s, P-Cipso); 126.9
140.8 (s, Cipso-Ph); 135.3 (d, 1JC−P = 52.2 Hz P-Cipso); 134.4 (d, 2JC−P
=
1
10.0 Hz, C PPh2Me); 133.9 (d, JC−P = 52.2 Hz P-Cipso); 133.3 (d,
3
2JC−P = 9.5 Hz, C PPh2Me); 130.2 (d, JC−P = 2.5 Hz, C PPh2Me);
(s, C CPh2); 115.1 (d, 2JC−P = 13.9 Hz, CHCPh2); 103.8 (d, 2JC−P
=
1
3
1.7 Hz, C5(CH3)5); 14.1 (d, JC−P = 44.5 Hz, PPh2CH3); 9.0 (s,
130.1 (d, JC−P = 2.5 Hz, C PPh2Me); 128.9 (s, C CPh2); 128.7 (s, C
C5(CH3)5) ppm. IR (cm−1): νCO 2035 (s); νPF 840 (s). MS (m/z,
CPh2); 128.1 (s, C PPh2Me); 128.0 (s, C CPh2); 127.9 (s, C PPh2Me);
127.8 (s, C CPh2); 126.1 (s, C CPh2); 125.6 (s, C CPh2); 123.0 (d,
6
referred to the most abundant isotopes): 735 [M]+. Anal. Calcd for
C38H39OF6IrP2 (880): C, 51.87; H, 4.47. Found: C, 51.92; H, 4.50.
Preparation of [IrCp*Cl{C(OH)CHCPh2}(PPh2Me)]OCF3SO3
(7). To an orange solution of 5 (120 mg, 0.16 mmol) in
dichloromethane (5 mL) was added trifluoromethanesulfonic acid
(17 μL, 0.19 mmol), and the mixture was stirred for 5 min. The red
solution obtained was concentrated, yielding a red oil that was washed
and precipitated with pentane (4 × 4 mL). Finally, the red solid that
was obtained was dried under vacuum. Yield: 128 mg (87%). 1H NMR
(CD2Cl2): δ 7.27−7.68 (m, 18H, PPh2CH3 + CPh22); 7.16 (s br, 1H,
Cβ-H); 7.03−7.10 (m, 2H, CPh2); 2.26 (d, 3H, JH−P = 10.2 Hz,
2
2JC−P = 17.7 Hz, Cα); 112.5 (s, Cγ); 94.8 (d, JC−P = 2.6 Hz,
C5(CH3)5); 59.1 (s, OCH3); 15.1 (d, 1JC−P = 39.5 Hz, PPh2CH3); 8.7
(s, C5(CH3)5) ppm. IR (cm−1): νCCC 1889 (w). MS (m/z, referred
to the most abundant isotopes): 785 [M + 1]+. Anal. Calcd for
C39H41OClIrP (784.4): C, 59.72; H, 5.27. Found: C, 59.89; H, 5.35.
Preparation of [IrCp*Cl{C(O)CHCPh2}(PPh2Me)] (5). An orange
solution of 3 (900 mg, 0.97 mmol) in dichloromethane (20 mL) was
treated with amine (1.16 mmol). The solution was stirred for 5 min at
room temperature, and then the solvent was removed by vacuum to
give an orange oil. This oil was treated with C6H6 to extract the
ammonium salts obtained in this reaction. The ammonium salts are
insoluble in this media, and the acyl complex 5 is totally soluble. The
1H NMR experiment of the isolated solid (the ammonium salts) in
dichloromethane shows different groups of signals, in agreement with
the presence of a mixture of ammonium salts. Thus, when Et3N was
used, the formation of [Et3NMe]PF6 was observed. 1H NMR
4
PPh2CH3); 1.66 (d, 15H, JH−P = 1.9 Hz, C5(CH3)5); ppm. 31P{1H}
NMR (CD2Cl2): δ −12.43 (s, PPh2CH3) ppm. 19F{1H} NMR
(CD2Cl2): δ −78.92 (s, CF3SO3). 13C{1H} NMR (CD2Cl2): δ 159.5
1
(s, Cγ); 133.7 (s, Cβ); 99.5 (s, C5(CH3)5); 13.8 (d, JC−P = 39.6 Hz,
PPh2CH3); 8.8 (s, C5(CH3)5) ppm, the other resonances were not
assigned because of the instability of the compound. IR (cm−1): νOH
3443 (w br). MS (m/z, referred to the most abundant isotopes): 771
[M]+, 735 [M − Cl]+.
3
(CD2Cl2): 3.25 (q, 6H, JH−H = 7.3 Hz, CH2); 2.89 (s, 3H, CH3);
3
1.32 (t, 9H, JH−H = 7.3 Hz, CH3) ppm. When Et2NH was used, a
In Situ Formation of 1,1-Diphenylethene and 3-Methyl-1,1,3−
triphenylindane. 1,1-Diphenylethene. To an orange solution of 5 (70
mg, 0.092 mmol) in dichloromethane-d2 (0.5 mL) was added
mixture (60/40) of [Et2NH(CH3)]PF6 and [Et2N(CH3)2]PF6 was
1
observed. H NMR (CD2Cl2) for [Et2NH(CH3)]PF6: 6.37 (s br, 1H,
N-H); 2.81 (q, 4H, 3JH−H = 7.1 Hz, CH2), 2.34 (s, 3H, N−CH3); 1.21
1
trifluoromethanesulfonic acid (9.4 μL, 0.10 mmol). In the H and
(t, 6H, 3JH−H = 7.2 Hz, CH3) ppm and for [Et2N(CH3)2]PF6: 3.25 (q,
31P{1H} NMR experiments was observed the formation of 7, which in
this acid media yielded, after 2 h, a new organometallic compound and
an organic substrate. The NMR data indicate that the organometallic
complex is [IrCp*Cl(CO)(PPh2Me)](OSO2CF3) (8) and the organic
compound is 1,1-diphenylethene.
4H, 3JH−H = 7.3 Hz, CH2), 2.94 (s, 6H, N-CH3); 1.30 (t, 6H, 3JH−H
=
7.3 Hz, CH3) ppm. The solvent of the orange solution was removed by
vacuum, giving a yellow solid that was washed with methanol (3 × 6
mL) and dried under vacuum. Yield: 350 mg (47%). 1H NMR (C6D6):
δ 7.67 (s, 1H, Cβ-H); 7.54−7.73 (m, 8H, Ph); 7.19−7.24 (m, 2H, Ph);
3-Methyl-1,1,3-triphenylindane. Trifluoromethanesulfonic acid
(34 μL, 0.36 mmol) was added to an orange solution of 5 (70 mg,
0.092 mmol) in dichloromethane (4 mL), and the mixture was stirred
overnight to give a brown solution. After the solvent was removed
under reduced pressure, a brown oil was obtained. This oil was treated
with diethyl ether, giving a precipitate, which was filtrated and washed
with pentane (2 × 2 mL). This solid was characterized as complex 8.
On the other hand, the diethyl ether solution was passed through a
silica column, giving a brown oil that was identified as 3-methyl-1,1,3-
triphenylindane.
2
6.95−7.10 (m, 10H, Ph); 1.88 (d, 3H, JH−P = 10.4 Hz, PPh2CH3);
1.27 (d, 15H, 4JH−P = 1.9 Hz, C5(CH3)5) ppm. 31P{1H} NMR (C6D6):
δ −10.88 (s, PPh2CH3) ppm. 13C{1H} NMR (C6D6): δ 219.0 (d, 2JC−P
= 13.0 Hz, Cα); 144.9 (s, Cipso-Ph); 143.2 (d, 3JC−P = 2.6 Hz, Cβ); 141.1
1
(s, Cipso-Ph); 136.5 (s, Cγ); 134.6 (d, JC−P = 53.4 Hz, P-Cipso); 134.5
(d, 2JC−P = 9.8 Hz, C PPh2Me); 133.1 (d, 2JC−P = 9.5 Hz, C PPh2Me);
1
132.9 (d, JC−P = 54.1 Hz, P-Cipso); 131.8 (s, C PPh2Me); 130.2 (d,
3
3JC−P = 2.4 Hz, C PPh2Me); 129.9 (d, JC−P = 2.4 Hz, C PPh2Me);
129.5 (s, C PPh2Me); 128.4 (s, C CPh2); 127.6−128.4 (some signals
1
are overlapped with the solvent signal); 127.3 (s, C CPh2); 127.2 (s, C
Data for 8·OSO2CF3 are as follows. H NMR (CD2Cl2): δ 7.50−
2
1
2
CPh2); 95.3 (d, JC−P = 2.8 Hz, C5(CH3)5); 14.0 (d, JC−P = 39.2 Hz,
PPh2CH3); 8.4 (s, C5(CH3)5) ppm. IR (cm−1): νCO 1577 (s). MS (m/
z, referred to the most abundant isotopes): 771 [M + 1]+, 735 [M −
7.70 (m, 10H, PPh2CH3); 2.40 (d, 3H, JH−P = 11.2 Hz, PPh2CH3);
4
1.80 (d, 15H, JH−P = 2.5 Hz, C5(CH3)5); ppm. 31P{1H} NMR
(CD2Cl2): δ −12.08 (s, PPh2CH3) ppm. The nature of 8 was
F
dx.doi.org/10.1021/om400565c | Organometallics XXXX, XXX, XXX−XXX

Organometallics
Article
confirmed by comparing its NMR data with those of the [IrCp*Cl-
(CO)(PPh2Me)]BPh4 complex recently reported17 and after a
metathesis reaction of 8 with an excess of NaBPh4 in methanol.
(3) (a) Cardin, D. J.; Cetinkaya, B.; Lappert, M. F. Chem. Rev. 1972,
72, 545−574. (b) Block, T. F.; Fenske, R. F.; Casey, C. P. J. Am. Chem.
́
Soc. 1976, 98, 441−443. (c) Ulrich, K.; Porhiel, E.; Peron, V.; Ferrand,
2
13C{1H} NMR (CD2Cl2) (not previously reported): δ 166.1 (d, JC−P
V.; Bozec, H. L. J. Organomet. Chem. 2000, 601, 78−86. (d) Andrada,
D. M.; Jimen
́
ez-Halla, J. O. C.; Sola, N. J. Org. Chem. 2010, 75, 5821−
= 14.3 Hz, CO); 132.6−133.3 (C PPh2Me); 129.4−129.8 (C
1
1
5836 and references therein. (e) Spessard, G. O.; Miessler, G. L.
Organometallic Chemistry; Prentice-Hall: Upper Saddle River, NJ,
1997; pp 323−326.
PPh2Me); 129.0 (d, JC−P = 61.7 Hz, Ci1pso); 127.6 (d, JC−P = 61.8
Hz, Cipso); 105.6 (s, C5(CH3)5); 15.1 (d, JC−P = 42.6 Hz, PPh2CH3);
9.4 (s, C5(CH3)5) ppm.
1
Data for 1,1-diphenylethene are as follows. H NMR (CD2Cl2): δ
(4) (a) Toomey, L. M.; Atwood, J. D. Organometallics 1997, 16,
490−493.
7.31−7.36 (m, 10H, Ph2); 5.47 (s, 2H, CH2) ppm. 13C{1H} NMR
(CD2Cl2): δ 150.6 (s, Cipso-Ph); 141.9 (s, Cipso-Ph); 128.6 (s, C Ph);
128.5 (s, C Ph); 128.1 (s, C Ph); 114.5 (s, CH2) ppm.
(5) (a) Davison, A.; Reger, D. L. J. Am. Chem. Soc. 1972, 94, 9237−
9238. (b) Cutler, A. R. J. Am. Chem. Soc. 1979, 101, 604−606.
(c) Bodner, G. S.; Smith, D. E.; Hatton, W. G.; Heah, P. C.; Georgiou,
S.; Rheingold, A. L.; Geib, S. J.; Hutchinson, J. Pl.; Gladysz, J. A. J. Am.
Chem. Soc. 1987, 109, 7688−7705.
1
Data for 3-methyl-1,1,3-triphenylindane are as follows. H NMR
(CD2Cl2): δ 7.00−7.36 (m, 19H, Ph); 3.39 (d, 1HB, system AB, 2JH−H
2
= 13.4 Hz CH2); 3.13 (d, 1HA, system AB, JH−H = 13.4 Hz, CH2);
1.56 (s, 3H, CH3) ppm. 13C{1H} NMR (CD2Cl2): δ 150.9 (s, CPh2);
149.8 (s, Cipso-Ph); 149.2 (s, CPhMe); 149.0 (s, Cipso-Ph); 148.0 (s,
Cipso-Ph); 125.4, 125.9, 126.0, 126.4, 127.3, 127.9, 128.2, 128.3, 129.0,
129.1 (all s, C Ph); 61.4 (s, CH2); 61.3 (s, CCPh2); 51.5 (s, CCPhMe);
29.2 (s, CH3) ppm.
(6) (a) Treichel, P. M.; Wagner, K. P. J. Organomet. Chem. 1975, 88,
199−206. (b) Green, M. L. H.; Mitchard, L. C.; Swanwick, M. G. J.
Chem. Soc. A 1971, 794−797.
(7) (a) Chisholm, M. H.; Clark, H. C.; Johns, W. S.; Ward, J. E. H.;
Yasufuku, K. Inorg. Chem. 1975, 14, 900−905. (b) O’Connor, J. M.;
Pu, L.; Rheingold, A. L. Organometallics 1988, 7, 2060−2062.
(c) Ching, C. S.; Kim, M.; Lee, M. K.; Lee, H. Organometallics
2003, 22, 3239−3244.
Preparation of [IrCp*Cl{C(NH2)CHCPh2}(PPh2Me)]PF6 (9). An
orange solution of 3 (450 mg, 0.48 mmol) in dichloromethane (10
mL) was treated with ammonia (30%; 38 μL, 0.53 mmol). The
solution was stirred for 90 min, and then the solvent was removed by
vacuum to give an orange oil that was precipitated and washed with
pentane (3 × 6 mL). Finally it was dried under vacuum. Yield: 362 mg
(8) Glueck, D. S.; Bergman, R. G. Organometallics 1991, 10, 1479−
1486.
(9) Cadierno, V.; Gimeno, J. Chem. Rev. 2009, 109, 3512−3560.
(10) The intermediate A evolved to 6. The allenylidene ligand in A
reacts with the water (1 equiv) released along the Selegue reaction.
This released water assembles the metallacumulene species A to
produce 6: Selegue, J. P. Organometallics 1982, 1, 217−218.
(11) Yamamoto, Y.; Sugawara, K.; Han, X. H. Dalton Trans. 2002,
195−211.
1
(82%). H NMR (CD2Cl2): δ 9.71 (s br, 1H, NH2); 8.26 (s br, 1H,
NH2); 7.37−7.62 (m, 16H, CPh2 + PPh2CH3); 7.13−7.18 (m, 2H,
CPh2); 7.07−7.12 (m, 2H, CPh2); 6.85 (s, 1H, Cβ-H); 2.19 (d, 3H,
2JH−P = 10.1 Hz, PPh2CH3); 1.61 (d, 15H, 4JH−P = 2.2 Hz, C5(CH3)5)
ppm. 31P{1H} NMR (CD2Cl2): δ −13.39 (s, PPh2CH3); −144.15
1
(sept, JP−F = 710.6 Hz, PF6) ppm. 13C{1H} NMR (CD2Cl2): δ 209.9
2
́
(d, JC−P = 11.9 Hz, Cα); 150.4 (s, Cγ); 139.3 (s, Cipso-Ph); 136.7 (s,
(12) Alvarez, E.; Paneque, M.; Petronilho, A. G.; Poveda, M. L.;
2
2
Cipso-Ph); 133.0 (d, JC−P = 9.9 Hz, C PPh2Me); 132.6 (d, JC−P = 9.7
Santos, L. L.; Carmona, E.; Mereiter, K. Organometallics 2007, 26,
Hz, C PPh2Me); 132.1 (d, 3JC−P = 2.7 Hz, Cβ-H); 132.0 (d, JC−P = 2.2
1231−1240.
3
Hz, C PPh2Me); 131.9 (d, JC−P = 2.8 Hz, C PPh2Me); 131.4 (s, C
(13) (a) Bernasconi, C. F.; Flores, F. X.; Sun, W. J. Am. Chem. Soc.
CPh2); 130.7 (d, 1JC−P = 43.1 Hz, P-Cipso); 130.6 (s, C CPh2); 130.4 (s,
C CPh2); 130.1 (d, 1JC−P = 43.7 Hz, P-Cipso); 129.6 (s, C CPh2); 129.4
(d, JC−P = 10.8 Hz, C PPh2Me); 128.9 (d, JC−P = 10.8 Hz, C PPh2Me);
1995, 117, 4875−4880. (b) Aumann, R.; Hinterding, P.; Kruger, C.;
̈
Goddard, R. J. Organomet. Chem. 1993, 459, 145−149. (c) O’Connor,
J. M.; Hiibner, K. J. Chem. Soc., Chem. Commun. 1995, 1209−1210.
(14) (a) Albertin, G.; Antoniutti, S.; Castro, J. Organometallics 2011,
30, 1558−1568. (b) Bianchini, C.; Casares, J. A.; Peruzzini, M.;
Romerosa, A.; Zanobini, F. J. Am. Chem. Soc. 1996, 118, 4585−4594.
(c) Grundy, K. R.; Jenkins, J. J. Organomet. Chem. 1984, 265, 77−85.
(15) Fox, M. A.; Whitesell, J. K. Organic Chemistry, 2nd ed.; Jones
and Bartlett: Sudbury, MA, 1994.
2
128.5 (s, C CPh2); 128.2 (s, C CPh2); 98.1 (d, JC−P = 2.2 Hz,
1
C5(CH3)5); 13.9 (d, JC−P = 41.8 Hz, PPh2CH3); 8.9 (s, C5(CH3)5)
ppm. IR (cm−1): νNH 3370 (m); νPF 840 (s). MS (m/z, referred to the
6
most abundant isotopes): 770 [M]+. Anal. Calcd for C38H41ClF6IrNP2
(915.36): C, 49.86; H, 4.51; N, 1.53. Found: C, 49.98; H, 4.57; N,
1.57.
(16) This reaction gave a mixture of several compounds that were
identified by 31P{1H} NMR experiments as 5, 6, A, and 7 (signal at
−12.4 ppm).
ASSOCIATED CONTENT
* Supporting Information
CIF files giving crystallographic data for compounds 3 and 6.
This material is available free of charge via the Internet at
http://pubs.acs.org.
■
S
(17) Talavera, M.; Bolano, S.; Bravo, J.; Castro, J.; García-Fontan
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AUTHOR INFORMATION
Corresponding Author
*E-mail for S.B.: bgs@uvigo.es.
Notes
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(21) Bianchini, C.; Dante, M.; Romerosa, A.; Zanobini, F.; Peruzzini,
M. Organometallics 1999, 18, 2376−2386.
The authors declare no competing financial interests.
(22) Perrin, D. D.; Armarego, W. L. F. Purification of Laboratory
Chemicals, 3rd ed.; Butterworth/ Heinemann: London/Oxford, 1988.
(23) SMART Version 5.054, Instrument control and data collection
software; Bruker Analytical X-ray Systems: Madison, WI, 1997.
(24) SAINT Version 6.01, Data Integration software package; Bruker
Analytical X-ray Systems: Madison, WI, 1997.
ACKNOWLEDGMENTS
We thank the University of Vigo CACTI services for collecting
X-ray data. S.B. thanks M. A. Esteruelas for fruitful discussions.
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(25) Sheldrick, G. M. SADABS. A Computer Program for Absorption
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dx.doi.org/10.1021/om400565c | Organometallics XXXX, XXX, XXX−XXX