Reactivity of octahedral η1-allenyl iridium toward hard nucleophiles

Article abstract of DOI:10.1021/om960261a

A labile octahedral (η¹-allenyl)iridium complex, (OC-6-42)-Ir(Cl)(PPh₃)₂(OTf)(CO)(η ¹-CHCCH₂) (2a), undergoes regioselective addition with water or alcohol at the allenyl central carbon to generate the (η³-2-hydroxyallyl) and (η³-2-alkoxyallyl)iridium complexes {Ir(Cl)-(PPh₃)₂(CO)[η³-CH ₂C(OR)CH₂]}(OTf) (R = H (3), Me (4a), Et (4b)), respectively. The complex 3 and the η³-oxa-TMM species Ir(Cl)(PPh₃)₂(CO)[η³-CH ₂C(O)CH₂] (5) constitutes a conjugate acid-base pair. Hydrolysis of the η³-alkoxyallyl complexes yields 3, which further transforms into the carbon-bound iridium enolate (OC-6-52)-{Ir(Cl)(PPh₃)₂(OH₂)(CO)[η ¹-CH₂C(O)CH₃]}-(OTf) (6). The reaction of 2a with ammonia results in the substitution of NH₃ for the triflate ligand instead of hydroamination to the allenyl ligand. The construction of the C-N bond, however, is alternatively achieved by replacing the alkoxy group in 4a or 4b with the amino group, leading to the formation of the N-protonated and N-alkylated η³-aza-TMM iridium {Ir(Cl)(PPh₃)₂(CO)[η³-CH ₂C(NR₂)CH₂]}(OTf) (R = H (7a), Et (Tb)).

Full text of DOI:10.1021/om960261a

Organometallics 1997, 16, 1159-1166
1159
Rea ctivity of Octa h ed r a l η1-Allen yl Ir id iu m tow a r d Ha r d
Nu cleop h iles†
Ray-Hsi Hsu, J wu-Ting Chen,* Gene-Hsiang Lee, and Yu Wang
Department of Chemistry, National Taiwan University, Taipei, Taiwan 106, Republic of China
Received April 3, 1996X
A labile octahedral (η1-allenyl)iridium complex, (OC-6-42)-Ir(Cl)(PPh3)2(OTf)(CO)(η1-
CHCCH2) (2a ), undergoes regioselective addition with water or alcohol at the allenyl central
carbon to generate the (η3-2-hydroxyallyl) and (η3-2-alkoxyallyl)iridium complexes {Ir(Cl)-
(PPh3)2(CO)[η3-CH2C(OR)CH2]}(OTf) (R ) H (3), Me (4a ), Et (4b)), respectively. The complex
3 and the η3-oxa-TMM species Ir(Cl)(PPh3)2(CO)[η3-CH2C(O)CH2] (5) constitutes a conjugate
acid-base pair. Hydrolysis of the η3-alkoxyallyl complexes yields 3, which further transforms
into the carbon-bound iridium enolate (OC-6-52)-{Ir(Cl)(PPh3)2(OH2)(CO)[η1-CH2C(O)CH3]}-
(OTf) (6). The reaction of 2a with ammonia results in the substitution of NH3 for the triflate
ligand instead of hydroamination to the allenyl ligand. The construction of the C-N bond,
however, is alternatively achieved by replacing the alkoxy group in 4a or 4b with the amino
group, leading to the formation of the N-protonated and N-alkylated η3-aza-TMM iridium
{Ir(Cl)(PPh3)2(CO)[η3-CH2C(NR2)CH2]}(OTf) (R ) H (7a ), Et (7b)).
In tr od u ction
to facilitate its addition to the η1-allenyl ligand. Com-
paring the η1-allenyl complexes with a class of newly
developed cationic η3-propargyl/η3-allenyl complexes,8
we find that the η1-allenyl species react with nucleo-
philes at a slower pace; the reaction scope is also less
general. The mechanistic rationale for such a discrep-
ancy still remains elusive and calls for more thorough
investigation.
Since the first η1-allenyl complex was prepared,4 the
chemistry of transition-metal allenyl complexes has
been continuously attracting research interest for more
than two decades. The greatest portion of research in
this area has focused on the synthetic aspect. Various
features of the allenyl ligands have been developed.5,8
Nevertheless, the reactivity of the (η1-allenyl)metal
complexes has been relatively overlooked. Recent stud-
ies on metal allenyl species reveal that the organic
ligands are subject to regioselective nucleophilic addi-
tion.6 Our previous study on a square-planar (η1-
allenyl)platinum complex indicates that the η1-allenyl
ligand is linear and undergoes hydroamination.3 It has
also been noted that the η1-allenyl ligand appears to be
inert to external attack by nucleophiles.7 We propose
that it may need the precoordination of the nucleophile
In this work, we report the preparation of a labile
octahedral η1-allenyl complex of iridium, (OC-6-42)-Ir-
(Cl)(PPh3)2(OTf)(CO)(η1-CHCCH2), and its reactions
with hard nucleophiles have been studied. We turn to
such a system not only because that changing metal will
allow us to examine the generality of the reactivity of
the η1-allenyl group in nucleophilic addition but also
because we wish to understand how the coordination
affects the reactivity. It is found that the six-coordinate
(η1-allenyl)iridium complex undergoes the regioselective
addition of water or alcohol to form the η3-hydroxyallyl
and η3-alkoxyallyl complexes, respectively. In contrast,
reactions with better nucleophiles such as ammonia and
amine derivatives result in substitution for the triflate
ligand instead. Such results suggest that both the
coordinating ability and the acidity of the nucleophile
should be crucial to the addition of (η1-allenyl)iridium.
The products of hydroamination are alternatively formed
from the unusual substitution reactions of the η3-
alkoxyallyl group with ammonia or amine at the central
carbon.
† Based on the M.S. thesis of R.-H.H., National Taiwan University,
1994. The η3-Oxatrimethylenemethane complex M[η3-CH2C(O)CH2] is
abbreviated as η3-oxa-TMM;1 η3-aza-TMM stands for the η3-azatrim-
ethylenemethane complex M[η3-CH2C(NR)CH2];2 M[η3-CH2C(NH2)CH2]
is referred to as N-protonated η3-azatrimethylenemethane; M[η3-CH2C-
(NRR′)CH2] (R, R′ ) alkyl, aryl) is N-alkylated (or -arylated) η3-
azatrimethylenemethane.3 The prefix OC-6-42 follows IUPAC nomen-
clature from: Nomenclature of Inorganic Chemistry: Recommendations;
Leigh, G. J ., Ed.; Blackwell: Oxford, U.K., 1990.
X Abstract published in Advance ACS Abstracts, February 1, 1997.
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S0276-7333(96)00261-0 CCC: $14.00 © 1997 American Chemical Society

1160 Organometallics, Vol. 16, No. 6, 1997
Hsu et al.
Sch em e 1
Resu lts a n d Discu ssion
species, although partial dissociation of triflate from 2a
cannot be excluded.
Syn th esis a n d Ch a r a cter iza tion of (η1-Allen yl)-
ir id iu m Com p lexes. (OC-6-43)-Ir(Cl)2(PPh3)2(CO)(η1-
CHCCH2) (1a ) and (OC-6-54)-Ir(Br)(Cl)(PPh3)2(CO)(η1-
CHCCH2) (1b) were prepared according to the literature
method with use of oxidative addition.4 The composi-
tions of 1a and 1b are indicated by mass spectrometry
and the elemental analysis, and the structures are
supported by spectroscopy and the ensuing chemical
transformations. Unlike the square-planar trans-Pt-
(Br)(PPh3)2(η1-CHCCH2), which reacts with equimolar
amounts of amine to form the N-alkylated (or arylated)
η3-aza-TMM species at 25 °C, there is no reaction
between complexes 1 and equimolar amine even at 60
°C. This result indicates that the linear η1-allenyl
ligand indeed does not undertake direct external nu-
cleophilic attack. The octahedral 1a and 1b, which
contain no labile ligand, are probably inert to the
substitution of amine and thus leave no chance for
subsequent addition of the allenyl group. In order to
pursue the support for this assertion, we prepared a
triflate derivative of the allenyliridium complex for
further study.
In order to know whether 2a could release the triflate
ion to form a η3-propargyl/η3-allenyl species, we have
deliberately examined the reaction of 1b with AgBF4
in CDCl3 at -40 °C. Within the first NMR measure-
ment, an intermediate 2b that clearly contains a η1-
allenyl ligand is detected. The sharp singlet in its 19F
NMR at -40 °C suggests that the BF4- ion may be free
or may be in a rapidly exchanging process in solution.10
Complex 2b is thus considered to be either the cationic
pentacoordinate species [Ir(Cl)(PPh3)2(CO)(η1-CHCCH2)]-
(BF4) or a pseudooctahedral complex. The similarity of
the NMR data between 2a and 2b suggests that 2b may
be in a tetragonal-pyramidal environment (Scheme 1).
Isolation of 2b is not feasible, because it decomposes
either in solution or upon recrystallization. Therefore,
2a has been used as the starting species throughout this
study.
Ad d ition of Wa ter a n d Alcoh ol to Ir (Cl)(P P h 3)2-
(OTf)(CO)(η1-CHCCH2) (2a ). In contrast to the halo
species 1a and 1b, the labile triflato complex 2a is
subject to nucleophilic addition, again indicating that
the coordination of nucleophile is crucial to the addition
process. The reaction of 2a with an equimolar amount
of water at 0 °C under nitrogen readily generates the
cationic (hydroxyallyl)iridium species {Ir(Cl)(PPh3)2-
(CO)[η3-CH2C(OH)CH2]}(OTf) (3). In the 1H NMR
spectrum of 3, a broad peak at δ 11.5 is ascribed to the
hydroxyl proton and the signals at δ 2.96 and 3.78 are
assigned to the anti and syn hydrogens of η3-allyl,
respectively. The characteristic 13C NMR data for the
terminal and central carbon atoms of the allyl ligand
are found at δ 50.4 and 168.3.
Single crystals of 3 are grown from CH2Cl2 and Et2O
cosolvent. The X-ray diffraction unequivocally confirms
the assigned structure of 3, which is shown in Figure
1. Complex 3 has a slightly distorted trigonal bipyra-
midal geometry. The chloride and carbonyl ligands are
at the axial positions. The allyl moiety in a η3 mode
sits in a tilted manner at the equatorial position. The
C3 atom approaches the metal toward the carbonyl side.
The four-member framework of MC3 folds along the axis
defined by the C2 and C4 atoms with the C2-C3-C4
and C2-Ir-C4 planes constituting a dihedral angle of
58(1)°. As a result, the allyl central carbon is substan-
tially more distant from the iridium center than the two
Treatment of 1b with equimolar amounts of AgOSO2-
CF3 leads to the formation of the triflato allenyl complex
(OC-6-42)-Ir(Cl)(PPh3)2(OTf)(CO)(η1-CHCCH2) (2a ). The
reaction of 1a and AgOTf was complicated, although the
triflate derivative was indeed detected with NMR
techniques. The solid form of 2a is stable under a dry
nitrogen atmosphere but tends to deteriorate in air. It
also suffers decomposition in solution rapidly. We did
not attempt to identify the decomposed residue. The
linear η1-allenyl ligand in 2a is soundly evidenced by
1
the H NMR signals at δ 3.93 (Hγ) and 5.66 (HR) in a
ratio of 2:1 and the 13C NMR signals at δ 55.2 (CR), 72.4
(Cγ), and 205.4 (Câ). The triflate group of 2a exhibits
its infrared absorptions at 1001, 1230, and 1317 cm-1
,
suggesting that such a triflate ion is in a coordinating
mode rather than acts as a counteranion.9 Other
spectral data for 2a such as infrared absorptions of νCO
and νCdCdC, and 31P NMR are comparable to those of
1b. The molar conductivities of 1b and 2a measured
in noncoordinating CH2Cl2 at 25 °C are 0.79 and 3.35
cm2 equiv-1 Ω-1, respectively. These data are substan-
tially smaller than the value 10.30 cm2 equiv-1 Ω-1 due
to the ionic complex 7a (vide supra) measured under
the same conditions. Accordingly, 2a is likely a neutral
(9) (a) Blake, D. M. J . Chem. Soc., Chem. Commun. 1974, 815. (b)
Lawrence, G. A. Chem. Rev. 1986, 86, 17.
(10) Smith, G.; Cole-Hamilton, D.-J .; Gregory, A. C.; Gooden, N. G.
Polyhedron 1982, 1, 97.

Reactivity of Octahedral (η1-Allenyl)iridium
Organometallics, Vol. 16, No. 6, 1997 1161
Sch em e 2
The complex 2a also reacts with alcohol in a similar
manner to yield the first iridium complexes with η3-2-
alkoxyallyl ligands, {Ir(Cl)(PPh3)2(CO)[η3-CH2(COR)-
CH2]}(OTf) (R ) Me (4a ), Et (4b)), in good yields
(Scheme 2). The complexes 4a and 4b decompose in air
even in the solid state. Their elemental data are not
satisfactory. We have mainly characterized 4a and 4b
by spectroscopic methods. The FAB mass analysis of
4a and 4b gives the molecular weights of the cations.
The 1H NMR signals of anti and syn hydrogens are
detected at δ 3.16 and 3.60 for 4a and δ 3.15 and 3.58
for 4b. The 13C NMR resonances of the terminal and
central carbon atoms of the allyl ligand are observed at
δ 48.8 and 168.1 for 4a and δ 49.0 and 167.9 for 4b,
respectively. These data are comparable to those for 3.
The methoxy protons of 4a appear at δ 3.78 and at δ
1.34 and 3.97 with a 3:2 ratio of integration for the
ethoxy protons of 4b. Other spectral data also closely
resemble those of 3. Therefore, the alkoxyallyl com-
plexes 4a and 4b are thought to have the similar
structural features similar to those of 3. Scheme 2
illustrates the convenient synthesis of substituted (η3-
allyl)iridium species by constructing the C-O bond
regioselectively at the allenyl central carbon. The
chemical discrepancy between 1a , 1b, and 2a toward
the nucleophiles is attributed to the difference in the
ligand lability.
Hydr olysis of Hydr oxyallyl an d Alkoxyallyl Com -
p lexes of Ir id iu m . The hydroxy group of 3 is moder-
ately acidic. Complex 3 can be transformed into the
neutral η3-oxa-TMM species Ir(Cl)(PPh3)2(CO)[η3-CH2C-
(O)CH2] (5) by treating with base. Addition of benzoic
acid or stronger acids to 5 yields 3. However, acetic acid
fails to protonate 5. Exposing complex 4a or 4b to air
leads to the transformation into the hydroxyallyl com-
plex 3 (vide supra) accompanied by the formation of the
corresponding alcohol. Complex 3 further slowly trans-
forms into the cationic (enolato)iridium species (OC-6-
52)-{Ir(Cl)(PPh3)2(H2O)(CO)[η1-CH2C(O)CH3]}(OTf) (6)
(Scheme 3). The structure of 6 has been determined
by X-ray diffraction and is shown in Figure 2. It shows
that 6 is six-coordinate and the enolate ligand is in a
carbon-bound keto form. An aquo ligand is located cis
to the enolate and trans to the carbonyl. The two
phosphines of 6 are disposed at trans positions.
F igu r e 1. ORTEP drawing of the cation of 3, {Ir(Cl)-
(PPh3)2(CO)[η3-CH2C(OH)CH2]}+. All hydrogen atoms are
omitted for clarity.
allyl terminal carbons, with D(Ir-C3) ) 2.34(1) Å, D(Ir-
C2) ) 2.22(1) Å, and D(Ir-C4) ) 2.23(1) Å. The hydroxy
group attaches to the central carbon C3 with D(C3-
O2) ) 1.33(1) Å, which is rather short in comparison
with the platinum analogue.7 The hydroxy hydrogen
is arbitrarily located at a fixed distance of 0.96 Å from
the oxygen atom.
The formation of 6 is presumably due to the reaction
of 3 with water. The entering water can facilitate the

1162 Organometallics, Vol. 16, No. 6, 1997
Hsu et al.
Sch em e 3
Sch em e 5
the thermodynamically more stable carbon-bound form
to the more reactive oxygen-bound form has not yet been
observed.11
Nu cleop h ilic Su bstitu tion of Alk oxya llyl Com -
p lexes. To our surprise, the reaction of 2a with
ammonia only results in substitution, yielding (OC-6-
42)-{Ir(Cl)(PPh3)2(NH3)(CO)(η1-CHCCH2)}(OTf) (8). The
product of hydroamination has not been observed. The
different reactivity of 2a with ammonia as compared to
that with water or alcohol may be attributed to the
acidity of the nucleophile. The better acidity of the
coordinated water or alcohol probably facilitates the
O-H bond activation. Besides, the results suggest that
the addition of octahedral allenyliridium is unlikely to
proceed via a highly reactive η3-propargyl/η3-allenyl
intermediate.
F igu r e 2. ORTEP drawing of the cation of 6, (OC-6-52)-
{Ir(Cl)(PPh3)2(H2O)(CO)[η1-CH2C(O)CH3]}+. All hydrogen
atoms are omitted for clarity.
Sch em e 4
Recalling that the η3-alkoxyallyl complexes 4a and 4b
are hydrolyzed to yield the η3-hydroxyallyl complex 3,
the reaction can be elucidated by an addition-elimina-
tion mechanism (Scheme 5). In other words, the
alkoxyallyl complexes may be transformed into the
hydroxyallyl complex via substitution at the allyl central
carbon, where the entering nucleophile is a water
molecule and the alcohol is the preferable leaving
member. Similar reactions in the platinum systems
have also been observed.12 These substitution reactions
present new chemical behavior for the η3-allyl com-
plexes. A good pπ-donating substituent at the central
η3-allyl carbon may prompt this carbon to be subject to
conversion of 3 to the η1-enol intermediate I followed
by a proton transfer to generate 6 (Scheme 4). The
hydrolysis of 3 to I is likely reversible. When a solution
of 4a or 4b is present with insufficient water, complex
6 is formed at a much slower pace at the expense of 4a
or 4b, but without the detection of 3. Our attempt to
establish the “aldol reaction” by reacting the (enolato)-
iridium species 6 or the (hydroxyallyl)iridium complex
3 with either aldehyde or silyl halide has not been
successful. Although complex 6 contains a weak aquo
ligand cis to the enolate ligand, tautomerization from
(11) (a) Burkhardt, E. R.; Doney, J . J .; Bergman, R. G.; Heathcock,
C. H. J . Am. Chem. Soc. 1987, 109, 2022. (b) Slough, G. A.; Bergman,
R. G.; Heathcock, C. H. J . Am. Chem. Soc. 1989, 111, 938. (c)
Burkhardt, E. R.; Bergman, R. G.; Heathcock, C. H. Organometallics
1990, 9, 30. (d) Hartwig, J . F.; Bergman, R. G.; Anderson, R. A.
Organometallics 1991, 10, 3326. (e) Stack, J . G.; Doney, J . J .; Bergman,
R. G.; Heathcock, C. H. Organometallics 1990, 9, 453.
(12) Tsai, F.-Y.; Chen, H.-W.; Chen, J .-T.; Lee, G.-H.; Wang, Y.
Submitted for publication.

Reactivity of Octahedral (η1-Allenyl)iridium
Organometallics, Vol. 16, No. 6, 1997 1163
Sch em e 6
nucleophilic attack. Such a reactivity is in contrast to
the chemistry of the common η3-allyl complexes with
nucleophiles, wherein the allyl ligand prefers to undergo
attack at a terminal carbon.13
Utilizing the strategy of Scheme 5, we succeeded in
constructing a C-N bond at the central allyl carbon.
The first examples of N-protonated and N-alkylated η3-
aza-TMM iridium complexes, {Ir(Cl)(PPh3)2(CO)[η3-
CH2C(NR2)CH2]}(OTf) (R ) H (7a ), Et (7b)), can thus
be prepared in nearly quantitative yields by the reac-
tions of 4a and 4b with NH3 and Et2NH, respectively
(Scheme 6). Such substitution reactions serve as an
pragmatic alternative methodology for C-N bond for-
mation with metal allenyl species. The complexes 7a
and 7b have been characterized by spectroscopy and
crystallography. The X-ray structures of both 7a and
7b are determined. The ORTEP drawing of complex
7a is shown in Figure 3 as being representative. The
lengths of the C-N bonds in both 7a and 7b are in the
range of substantial double-bonding. The folding angle
of the MC3 skeleton, θ, is 49.9(5)° in 7a and 38.9(4)° in
7b, which are the smallest measured values among the
related species.
F igu r e 3. ORTEP drawings of the cation of 7a , {Ir(Cl)-
(PPh3)2(CO)[η3-CH2C(NH2)CH2]}+: (A) top view; (B)side
view. All hydrogen atoms are omitted for clarity.
Str u ctu r a l Ch a r a cter istic of Hyd r oxya llyl, η3-
oxa -TMM, N-P r oton a ted a n d N-Alk yla ted η3-a za -
TMM Com p lexes. The η3-allyl, metallacyclobutane,
and the η3-TMM-related complexes all have a common
four-membered MC3 skeleton. The structure of these
species can be characterized by measuring the distance
from the central carbon atom to the metal D(M-Cc) and
the dihedral angle θ defined by the Ct-Cc-Ct and Ct-
M-Ct planes:
bond of an η3-allyl may be as strong as the M-Ct
bonds. A substituent which has a good pπ property at
the allyl central carbon may cost the interaction of the
M-Cc bond. As a result, D(M-Cc) increases and θ
decreases.
Table 1 collects the characteristic structural data of
several η3-allyl derivatives, η3-oxa-TMM, N-protonated
and N-alkylated η3-aza-TMM complexes of iridium. The
η3-2-hydroxyallyl complex 3 has a substantially longer
M-Cc bond and smaller θ than those of an unsubsti-
tuted allyliridium complex.13 The η3-oxa-TMM complex
5, which contains a CcdO double bond has an even
longer D(M-Cc) and smaller value of θ than those of 3.
The data for D(Ct-Cc) and Ct-Cc-Ct also support that
the pπ-pπ interaction in the CdO bond occurs at the
expense of the pπ-pπ interaction in the allyl moiety.
On the basis of the structural parameters, we classify
7a to be the N-protonated η3-aza-TMM and 7b to be the
N-alkylated η3-aza-TMM complex. The η3-oxa-TMM
and N-protonated and N-alkylated η3-aza-TMM deriva-
tives may be envisaged as a class of stable intermediate
species between the η3-allyl and metallacyclobutane
groups.
These structural features reflect the folding degree of
the MC3 moiety. The metallacyclobutane has a large
D(M-Cc) and small θ value. In fact, there is no bond
between the metal and the central carbon in metalla-
cyclobutane. An η3-allyl compound generally has rela-
tively small D(M-Cc) and relatively large θ. The M-Cc
(13) Kaduk, J . A.; Poulos, A. T.; Ibers, J . A. J . Organomet. Chem.
1977, 127, 245.
(14) Chen, J .-T.; Chen, Y.-K.; Chu, J .-B.; Lee, G.-H.; Wang, Y.
Submitted for publication.

1164 Organometallics, Vol. 16, No. 6, 1997
Hsu et al.
Ta ble 1. Im p or ta n t Str u ctu r a l P a r a m eter s for th e
MC3 Sk eleton in
of hexane/Et2O resulted in the precipitation of a pinkish
microcrystalline product in 84% yield (468 mg). For 1a : IR
{Ir (Cl)(P P h 3)2(CO)[η3-CH2C(X)CH2]}+
(KBr pellet) νCdCdC 1923 cm-1, νCO 2048 cm-1 31P NMR (CDCl3)
;
δ -12.8; 1H NMR (CDCl3) δ 3.51 (2H, dt, J H-H ) 6.3 Hz, J P-H
) 3.3 Hz, CH2), δ 5.15 (1H, tt, J H-H ) 6.3 Hz, J P-H ) 2.5 Hz,
CH), δ 7.2-7.9 (30H, m, phenyl); 13C NMR (CDCl3) δ 68.2 (s,
CH2), 68.7 (t, J P-C ) 7.2 Hz, CH), 127-135 (phenyl), 159.7 (t,
J P-C ) 7.2 Hz, CO), 206.5 (t, J P-C ) 3.5 Hz, dCd); FAB MS
M-Ct
(Å)
M-Cc
(Å)
Ct-Cc Cc-Ct-Cc C-X
θb
X
(Å)
(deg)
(Å)
(deg) ref
H
2.28(1) 2.24(1) 1.38(3)
2.25(1) 1.40(3)
125(2)
1.0
65.1
13
OH
O
2.22 (1) 2.34(1) 1.42(2)
2.23(1) 1.40(2)
117(1)
1.33(1) 58(1)
a
(m/z) 819.3 (M+
-
81Br). For 1b: IR (KBr pellet) νCdCdC 1920
31P NMR (CDCl3) δ -16.1; 1H NMR
cm-1, νCO 2055 cm-1
;
2.169 (9) 2.561(9) 1.48(2)
2.184(9) 1.50(1)
106.6(8) 1.21(2) 41
1
(CDCl3) δ 3.57 (2H, dt, J H-H ) 6.2 Hz, J P-H ) 3.4 Hz, CH2),
5.31 (1H, tt, J H-H ) 6.2 Hz, J P-H ) 2.5 Hz, CH), 7.2-8.0 (30H,
m, phenyl); 13C NMR (CDCl3) δ 68.5 (s, CH), 70.5 (s, CH2),
127-135 (phenyl), 159.4 (t, J P-C ) 8.5 Hz, CO), 206.0 (s, dCd);
NH2
NEt2
2.182 (5) 2.442(5) 1.431(7) 111.6(4) 1.319(7) 49.9(5)
2.203(5) 1.441(7)
a
2.161 (4) 2.567(4) 1.457(6) 106.2(3) 1.297(5) 38.9(4)
2.173(4) 1.462(6)
a
FAB MS (m/z) 901 (M+), 863.2 (M+
- -
37Cl), 819.2 (M+ 81Br).
(OC-6-42)-Ir (Cl)(P P h 3)2(OSO2CF3)(CO)(η1-CHCCH2) (2a).
To a mixture consisting of 1b (190 mg) and AgOTf (60 mg, 1.1
equiv) was added N2-degassed dry CH2Cl2 (15 mL) at -20 °C.
The solution was stirred for 30 min to allow the complete
precipitation of AgBr. After AgBr was removed by filtration,
the solution was concentrated. Addition of degassed dry Et2O
to the solution resulted in a whitish yellow solid product. The
isolated yield of 2a was 66% (135 mg). The elemental analysis
was not acquired, for purification by recrystallization always
led to decomposition. IR (KBr pellet): νOTf 1001, 1230, 1317
NMePh 2.19 (1) 2.50(1) 1.40(2)
2.21(1) 1.45(2)
110(1)
1.32(2) 47(5)
14
14
NPh2
2.15 (3) 2.54(3) 1.41(4)
2.18(3) 1.54(4)
105(2)
1.31(3) 45(5)
a
b
This work. θ stands for the dihedral angle between the Ct-
Cc-Ct and Ct-M-Ct planes.
Con clu sion s
The labile octahedral (η1-allenyl)iridium complex (OC-
6-42)-Ir(Cl)(PPh3)2(OTf)(CO)(η1-CHCCH2) undergoes re-
gioselective CsO bond formation with water or alcohol
to form the first iridium η3-2-hydroxy- and η3-2-alkoxy-
allyl complexes, {Ir(Cl)(PPh3)2(CO)[η3-CH2C(OR)CH2]}-
(OTf) (R ) H, alkyl). The reaction of (OC-6-42)-
Ir(Cl)(PPh3)2(OTf)(CO)(η1-CHCCH2) with ammonia yields
the product of substitution {(OC-6-42)-Ir(Cl)(PPh3)2-
(NH3)(CO)(η1-CHCCH2)}(OTf) instead of that of hy-
droamination to the allenyl ligand. These contrary
results suggest that both the coordination and the
acidity of the added nucleophile may be crucial to the
addition to the metal η1-allenyl species. The CsN bond
formation at the central allenyl carbon can be alterna-
tively established by the rare amino substitution for the
alkoxy group at the central carbon of the η3-alkoxyallyl
complexes. The products are identified to be the pro-
tonated or alkylated η3-aza-TMM iridium complexes {Ir-
(Cl)(PPh3)2(CO)[η3-CH2C(NR2)CH2]}(OTf), which con-
stitute a class of stable intermediates between the metal
η3-allyl and metallacyclobutane species. The nucleo-
philic substitution at the central carbon of the η3-2-
alkoxyallyl complexes presents chemical features new
to allyl chemistry.
cm-1, νCdCdC 1928 cm-1, νCO 2063 cm-1 31P NMR (CDCl3): δ
.
-10.0. 1H NMR (CDCl3): δ 3.93 (2H, dt, J H-H ) 6.0 Hz, J P-H
) 4.1 Hz, CH2), 5.66 (1H, tt, J H-H ) 6.0 Hz, J P-H ) 3.0 Hz,
CH), 7.3-8.0 (30H, m, phenyl). 13C{1H} NMR (CDCl3): δ 55.2
(dt, J C-H ) 174 Hz, J P-C ) 8.5 Hz, CH), 72.4 (t, J C-H ) 162
Hz, CH2), 127-135 (phenyl), 158.6 (t, J P-C ) 8.4 Hz, CO), 205.4
(t, J P-C ) 3.3 Hz, dCd).
[Ir (Cl)(P P h 3)2(CO)(η1-CHCCH2)](BF 4) (2b). Refer to the
paragraph for 2a for the synthesis; spectra were taken at -40
°C. 31P NMR (CDCl3): δ -7.1. 1H NMR (CDCl3): δ 3.98 (2H,
CH2), 5.92 (1H, CH), 7.3-8.0 (m, phenyl). 13C NMR (CDCl3):
δ 51.5 (t, J P-C ) 6.9 Hz, CH), 72.7 (s, CH2), 127-135 (phenyl),
157.3 (t, J P-C ) 6.9 Hz, CO), 206.3 (s, dCd). 19F NMR (CDCl3,
233 K): δ -155 (s, BF4).
{Ir (Cl)(P P h 3)2(CO)[η3-CH2C(OH)CH2]}(OTf) (3). Com-
plex 2a was prepared in situ from 1 (140 mg) and AgOTf (45
mg, 1.1 equiv) in dry CH2Cl2 at -20 °C. After removal of AgBr
precipitate, the filtrate was warmed to 0 °C and water was
added (5.6 µL, 2.0 equiv). The reaction was allowed to continue
for 30 min at 0 °C. The solution then was filtered again and
concentrated. Addition of hexane provided product in 78%
isolated yield (120 mg). Single crystals suitable for X-ray
diffraction were grown by slowly diffusing pentane into a CH2-
Cl2 solution of complex 3 at 5 °C. IR (KBr pellet): νOTf 1298
cm-1, νCO 2048 cm-1
.
31P NMR (CDCl3): δ -12.8. 1H NMR
(CDCl3): δ 2.96 (2H, ddd, J H-H ) 4.56 Hz, J P-H ) 2.55, 9.51
Hz, Hanti), 3.78 (2H, s, br, Hsyn), 7.3-7.6 (30H, m, phenyl), 11.54
(1H, s, OH). 13C NMR (CDCl3): δ 50.4 (dd, J P-C ) 2.3, 40 Hz,
Ct), 126-135 (phenyl), 159.0 (t, J P-C ) 8.7 Hz, CO), 168.3 (s,
Cc).
Exp er im en ta l Section
Gen er a l Con sid er a tion s. The IR spectra were recorded
on a Bio-Rad FTS-40 spectrophotometer. The NMR spectra
were routinely measured on Bruker ACE-200 and ACE-300
spectrometers. For the 31P NMR spectra, spectrometer fre-
quencies of 81.015 and 121.49 MHz were employed, respec-
tively; chemical shifts are given in ppm (δ) relative to 85%
H3PO4 in CDCl3. The corresponding frequencies for 13C NMR
spectra were at 50.32, 75.47, and 125.76 MHz for the respective
spectrometers. Mass spectrometric analyses were collected on
a J EOL SX-102A spectrometer. Elemental analyses were done
on a Perkin-Elmer 2400 CHN analyzer.
Syn th esis a n d Ch a r a cter iza tion . (OC-6-43)-Ir (Cl)2-
(P P h 3)2(CO)(η1-CHCCH2) (1a ) a n d (OC-6-54)-Ir (Br )(Cl)-
(P P h 3)2(CO)(η1-CHCCH2) (1b).4 To a dry CH2Cl2 solution
containing trans-Ir(CO)(Cl)(PPh3)2 (485 mg) was added prop-
argyl bromide (85% in 0.1 mL, 1.5 equiv) under dry N2 at 0
°C. The yellow reaction solution turned to orange after 30 min.
The solution was then concentrated and filtered. Introduction
{Ir (Cl)(P P h 3)2(CO)[η3-CH2C(OR)CH2]}(OTf) (R ) Me
(4a ), Et (4b)). Complexes 4a and 4b were prepared according
to a procedure used for preparing 3, except that methanol or
ethanol was employed instead of water. The isolated yields
were 65% for 4a and 50% for 4b. Recrystallization would
cause decomposition. Selected spectral data for 4a : IR (KBr
pellet) νOTf 1266 cm-1, νCO 2052 cm-1 31P NMR (CDCl3) δ
;
-13.9; 1H NMR (CDCl3) δ 3.16 (2H, dd, J H-P ) 8.7 Hz, Hanti),
3.60 (2H, s, br, Hsyn), 3.78 (3H, s, OCH3), 7.3-7.7 (30H, m,
phenyl); 13C NMR (CDCl3) δ 48.8 (d, J P-C ) 40 Hz, Ct), 75.6
(s, OCH3), 127-134 (phenyl), 159.0 (t, J P-C ) 8.4 Hz, CO),
168.1 (s, Cc). For 4b: IR (KBr pellet) νOTf 1266 cm-1, νCO 2045
cm-1 31P NMR (CDCl3) δ -14.0; 1H NMR (CDCl3) δ 1.34 (3H,
;
t, J H-H ) 6.9 Hz, CH3), 3.15 (2H, dd, J H-P ) 6.7 Hz, Hanti),
3.58 (2H, s, br, Hsyn), 3.97 (2H, q, J H-H ) 6.9 Hz, CH2CH3),
7.3-7.6 (30H, m, phenyl); 13C NMR (CDCl3) δ 13.7 (s,

Reactivity of Octahedral (η1-Allenyl)iridium
Ta ble 2. X-r a y Cr ysta l P a r a m eter s a n d Da ta Collection Deta ils for Com p lexes 3, 6, 7a , a n d 7b
7a 7b
C41H35O5P2SF3IrCl‚CH2Cl2 C41H37O6P2SF3IrCl‚CH2Cl2 C41H36NO4P2SF3IrCl‚CH2Cl2 C45H44NO4P2SF3IrCl‚CH2Cl2
Organometallics, Vol. 16, No. 6, 1997 1165
3
6
formula
fw
1071.34
1089.36
0.03 × 0.25 × 0.25
P1h
1070.36
0.15 × 0.4 × 0.45
P1h
1126.47
0.2 × 0.5 × 0.5
P1h
cryst dimens, mm 0.1 × 0.15 × 0.35
space group
a, Å
P1h
10.060(5)
15.030(2)
15.355(2)
111.69(1)
98.01(2)
89.02(2)
2135(1)
2
11.099(2)
11.627(2)
18.659(4)
88.36(2)
88.53(2)
67.814(2)
2228.5(8)
2
12.842(3)
12.989(3)
13.589(5)
89.85(2)
92.98(3)
106.66(2)
2168(1)
2
12.502(2)
13.051(3)
15.781(2)
105.69(2)
89.85(1)
109.43(2)
2326.9(7)
2
b, Å
c, Å
R, deg
â, deg
γ, deg
V, Å3
Z
F(calcd), Mg m-3 1.665
1.623
1078
1.639
976
1.542
1040
F(000)
1088
radiation, λ, Å
Mo KR, 0.7107
Mo KR, 0.7107
Mo KR, 0.7107
Mo KR, 0.7107
T, K
298
298
298
298
µ, mm-1
transmissn
max 2θ, deg
hkl
3.36
0.78-1.0
45
3.34
0.78-1.0
45
(11,12,(20
5836
3.30
0.75-1.0
50
(15,15,(16
7632
3.08
0.57-1.0
50
(13,15,(18
8202
(10,16,(15
no. of rflns measd 5584
no. of rflns obsd
no. of variables
R(F)
Rw(F)
S
4801 (>2.0σ)
4385 (>2.0σ)
6446 (>2.0σ)
7214 (>2.0σ)
451
523
539
551
0.048
0.060
1.10
0.062
0.062
3.01
0.031
0.026
1.95
0.029
0.023
2.23
(∆/σ)max
0.006
0.027
0.042
0.019
Ta ble 3. Selected Bon d Dista n ces (Å) a n d An gles (d eg)
{Ir(Cl)(PPh3)2(CO)[η3-CH2C(OH)CH2]}(OTf) (3)
Ir-Cl(1)
Ir-P1
Ir-P2
2.370(3)
2.395(3)
2.389(3)
Ir-C(1)
Ir-C2
Ir-C3
1.86(1)
2.22(1)
2.34(1)
Ir-C4
2.23(1)
1.11(1)
1.42(2)
C3-C4
C3-O2
1.40(2)
1.33(1)
C1-O1
C2-C3
Cl1-Ir-P1
Cl1-Ir-P2
Cl1-Ir-C1
Cl1-Ir-C2
Cl1-Ir-C3
Cl1-Ir-C4
P1-Ir-P2
P1-Ir-C1
91.5(1)
82.7(1)
176.0(4)
85.8(3)
101.4(3)
87.2(3)
112.5(1)
89.3(4)
P1-Ir-C2
P1-Ir-C3
P1-Ir-C4
P2-Ir-C1
P2-Ir-C2
P2-Ir-C3
P2-Ir-C4
156.1(3)
122.3(3)
90.6(3)
C1-Ir-C2
C1-Ir-C3
C1-Ir-C4
C2-Ir-C3
C2-Ir-C4
C3-Ir-C4
Ir-C1-O1
Ir-C2-C3
95.0(5)
81.4(5)
96.7(5)
36.2(4)
65.6(4)
35.6(4)
178(1)
Ir-C3-C2
Ir-C3-C4
Ir-C3-O2
C2-C3-C4
C2-C3-O2
C4-C3-O2
Ir-C4-C3
67.2(6)
67.9(6)
122.3(8)
117(1)
93.4(4)
90.7(3)
124.8(3)
154.9(3)
122(1)
119(1)
76.5(7)
76.6(6)
(OC-6-52)-{Ir(Cl)(PPh3)2(H2O)(CO)[η1-CH2C(O)CH3]}(OTf) (6)
Ir-Cl(1)
Ir-P1
Pt-P2
2.458(4)
2.433(4)
2.415(5)
Ir-C(1)
Ir-C2
1.76(2)
2.13(2)
Ir-O2
C1-O1
C2-C3
2.10(1)
1.18(2)
1.58(3)
C3-C4
C3-O3
1.63(3)
1.17(2)
Cl1-Ir-P1
Cl1-Ir-P2
Cl1-Ir-C1
Cl1-Ir-C2
Cl1-Ir-O2
87.0(2)
94.2(2)
86.1(5)
172.4(5)
88.4(3)
P1-Ir-P2
P1-Ir-C1
P1-Ir-C2
P1-Ir-O2
P2-Ir-C1
178.6(2)
91.8(5)
88.8(4)
87.1(3)
88.9(5)
C1-Ir-C2
P2-Ir-C2
P2-Ir-O2
C2-Ir-O2
Ir-C1-O1
100.4(7)
89.9(4)
92.3(3)
85.0(5)
175(1)
Ir-C2-C3
C2-C3-C4
C2-C3-O3
C4-C3-O3
C1-Ir-O2
111(1)
105(2)
131(2)
124(2)
174.5(6)
{Ir(Cl)(PPh3)2(CO)[η3-CH2C(NH2)CH2]}(OTf) (7a )
Ir-Cl(1)
Ir-P1
Ir-P2
2.385(1)
2.394(2)
2.417(1)
Ir-C(1)
Ir-C2
Ir-C3
1.836(5)
2.182(5)
2.442(5)
Ir-C4
2.203(5)
1.144(6)
1.431(7)
C3-C4
C3-N
1.441(7)
1.319(7)
C1-O1
C2-C3
Cl1-Ir-P1
Cl1-Ir-P2
Cl1-Ir-C1
Cl1-Ir-C2
Cl1-Ir-C3
Cl1-Ir-C4
P1-Ir-P2
P1-Ir-C1
84.00(5)
93.5(5)
179.6(2)
86.3(1)
99.4(1)
84.8(2)
110.24(5)
95.7(2)
P1-Ir-C2
P1-Ir-C3
P1-Ir-C4
P2-Ir-C1
P2-Ir-C2
P2-Ir-C3
P2-Ir-C4
90.5(1)
124.5(1)
154.2(1)
86.3(1)
159.1(1)
124.6(1)
93.6(1)
C1-Ir-C2
C1-Ir-C3
C1-Ir-C4
C2-Ir-C3
C2-Ir-C4
C3-Ir-C4
Ir-C1-O1
Ir-C2-C3
94.0(2)
81.1(2)
95.6(2)
35.5(2)
65.6(2)
35.7(2)
179.0(4)
82.2(3)
Ir-C3-C2
Ir-C3-C4
Ir-C3-N
C2-C3-C4
C2-C3-N
C4-C3-N
Ir-C4-C3
62.3(3)
63.1(3)
130.0(4)
111.6(4)
123.7(4)
122.1(5)
81.2(3)
{Ir(Cl)(PPh3)2(CO)[η3-CH2C(NEt2)CH2]}(OTf) (7b)
Ir-Cl(1)
Ir-P1
2.395(1)
2.424(1)
2.438(1)
1.827(4)
Ir-C2
Ir-C3
Ir-C4
C4-N
2.173(4)
2.161(4)
2.567(4)
1.297(5)
C5-N
C7-N
C1-O1
C2-C4
1.470(6)
1.487(6)
1.132(5)
1.457(6)
C3-C4
C5-C6
C7-C8
1.462(6)
1.509(7)
1.489(7)
Ir-P2
Ir-C(1)
Cl1-Ir-P1
Cl1-Ir-P2
Cl1-Ir-C1
Cl1-Ir-C2
Cl1-Ir-C3
Cl1-Ir-C4
P1-Ir-P2
P1-Ir-C1
P1-Ir-C2
85.95(4)
92.88(4)
177.3(1)f
85.4(1)
P1-Ir-C3
P1-Ir-C4
P2-Ir-C1
P2-Ir-C2
P2-Ir-C3
P2-Ir-C4
C1-Ir-C2
C1-Ir-C3
C1-Ir-C4
91.3(1)
124.8(9)
87.2(1)
95.0(1)
160.2(1)
126.29(9)
92.0(2)
92.6(2)
80.3(1)
C2-Ir-C3
C2-Ir-C4
C3-Ir-C4
C4-N-C5
C4-N-C7
C5-N-C7
Ir-C1-O1
Ir-C2-C4
Ir-C3-C4
65.2(2)
34.5(2)
34.7(1)
122.3(4)
122.1(3)
115.5(3)
176.4(3)
87.7(2)
88.0(2)
Ir-C4-C2
Ir-C4-C3
Ir-C4-N
C2-C4-C3
C2-C4-N
C3-C4-N
N-C5-C6
N-C7-C8
57.7(2)
57.3(2)
143.7(3)
106.2(3)
126.8(4)
125.7(4)
111.7(4)
111.9(4)
86.5(1)
97.52(9)
108.40(4)
96.6(1)
155.4(1)

1166 Organometallics, Vol. 16, No. 6, 1997
Hsu et al.
OCH2CH3), 49.0 (d, J P-C ) 40 Hz, Ct), 67.2 (s, OCH2), 127-
134 (phenyl), 159.3 (t, J P-C ) 8.6 Hz, CO), 167.9 (s, Cc).
Ir (Cl)(P P h 3)2(CO)[η3-CH2C(O)CH2] (5).1 To CDCl3 (1 mL)
containing 3 (30 mg) was added Et3N (5 µL) at 25 °C. The
solution was stirred for 10 min. A white solid in 71% yield
(19 mg) was recovered by recrystallization. 31P NMR (CDCl3):
δ -10.5. 1H NMR (CDCl3): δ 2.47 (2H, m, J H-H ) 7.9 Hz,
CH2), 2.62 (2H, t, J H-H ) 7.9 Hz). 13C NMR (CDCl3): δ 37.1
(s, Ct), 127-135 (phenyl), 164.4 (t, J P-C ) 4.0 Hz, CO), 197.2
(s, Cc).
(O C-6-42)-{I r (C l)(P P h 3 )2 (N H 3 )(C O )(η1 -C H C C H 2 )}-
(OTf) (8). To a mixture containing 1b (250 mg, 0.28 mmol)
and AgOTf (1.1 equiv) was added 15 mL of N2-degassed dry
CH2Cl2 at -30 °C followed by NH4OH (32 µL, 1 equiv). The
reaction solution was stirred at 0 °C for 1 h. After AgBr was
removed by filtration, the reaction solution was concentrated.
The addition of degassed dry Et2O to the solution resulted in
a yellow solid product. The isolated yield of 8 was 70% (126
mg) after recrystallization. IR (KBr pellet): νCdCdC 1925 cm-1
νCO 2070 cm-1 31P NMR (CDCl3): δ -14.0. 1H NMR (CDCl3):
,
.
(OC-6-52)-{Ir (Cl)(P P h 3)2(H 2O)(CO)[η1-CH 2C(O)CH 3]}-
(OTf) (6). Complex 4a or 4b was left in solution under
ambient conditions for days. A grayish solid product was
precipitated by introducing hexane into the solution. The
isolated yield was 70%. Single crystals suitable for X-ray
diffraction were grown by slowly diffusing pentane into a CH2-
Cl2 solution of complex 6 at 5 °C. IR (KBr pellet): νOTf 1295
δ 2.76 (3H, br, NH3), 3.67 (2H, dt, J H-H ) 6.4 Hz, J P-H ) 3.7
Hz, CH2), 6.10 (1H, tt, J H-H ) 6.4 Hz, J P-H ) 2.8 Hz, CH),
7.2-8.0 (30H, m, phenyl). 13C NMR (CDCl3): δ 56.1 (t, J P-C
) 7.8 Hz, CH), 69.2 (s, CH2), 118-135 (phenyl), 157.4 (t, J P-C
) 7.4 Hz, CO), 208.0 (s, dCd). FAB MS (m/z) 819.4 (M+).
Anal. Calcd for IrC43H40O4ClNP2SF3: C, 49.94; H, 3.68; N,
1.42. Found: C, 49.52; H, 3.68; N, 1.14.
X-r a y Cr ysta llogr a p h ic An a lysis. Diffraction data were
measured at 298 K on a Nonius CAD-4 diffractometer with
graphite-monochromatized Mo KR radiation. Cell parameters
were determined by a least-squares fit on 25 reflections.
Intensity data were corrected for absorption on the basis of
an experimental ψ rotation curve. The refinement procedure
was by a full-matrix least-squares method, including all the
non-hydrogen atoms anisotropically. Hydrogen atoms were
fixed at the ideal geometry and a C-H distance of 1.0 Å; their
isotopic thermal parameters were fixed to the values of the
attached carbon atoms at the convergence of the isotropic
refinement. Atomic scattering factors were taken from ref 15.
Computing programs are from the NRCC SDP VAX package.16
Crystallographic data and selected bond parameters of 3, 6,
7a , and 7b are collected in Tables 2 and 3, respectively. Other
detailed data are supplied in the Supporting Information.
cm-1, νCO 1698, 2050 cm-1
.
31P NMR (CDCl3): δ 4.7. 1H NMR
(CDCl3): δ 1.29 (3H, s, CH3), 3.13 (2H, t, J P-H ) 3.8 Hz, CH2),
5.63 (2H, s, H2O), 7.3-7.6 (30H, m, phenyl). 13C NMR
(CDCl3): δ 27.4 (s, CH3), 29.4 (t, J P-C ) 3.4 Hz, CH2), 127-
135 (phenyl), 158.5 (t, J P-C ) 10.4 Hz, terminal CO), 210.8 (s,
enolate CO).
{Ir (Cl)(P P h 3)2(CO)[η3-CH2C(NR2)CH2]}(OTf) (R ) H
(7a ), Et (7b)). To a degassed dry CH2Cl2 solution containing
4a (90 mg) was added concentrated NH4OH (6.0 µL, 2 equiv
of NH3). After 15 min of stirring, the solution was concen-
trated to precipitate a light green product. The isolated yield
was 70%. 7b was prepared from 4a (or 4b) and Et2NH by a
similar procedure. Single crystals suitable for X-ray diffraction
were grown by slowly diffusing pentane into a CH2Cl2 solution
of either 7a or 7b at 5 °C. Selected spectral data for 7a : IR
(KBr pellet) νOTf 1284 cm-1, νCdN 1640 cm-1, νCO 2048 cm-1
;
1
31P NMR (CDCl3) δ -12.6; H NMR (CDCl3) δ 2.52 (2H, dd,
J H-H ) 7.4 Hz, J H-P ) 10.1 Hz, Hanti), 3.01 (2H, s, br, Hsyn),
7.07 (2H, s, NH2), 7.2-7.4 (30H, m, phenyl); 13C NMR (CDCl3)
Ack n ow led gm en t. We thank the National Science
Council, Taiwan, ROC, for financial support.
δ
34.3
(dd, J P-C ) 2.4, 52.5 Hz, Ct) 128-134 (phenyl), 161.4 (t, J P-C
) 8.2 Hz, CO), 172.8 (t, J P-C ) 3.1 Hz, Cc). Anal. Calcd for
IrC41H36O4ClNP2SF3: C, 50.00; H, 3.68. Found: C, 49.30; H,
Su ppor tin g In for m ation Available: Fully labeled ORTEP
drawings and tables giving complete crystal data, complete
bond lengths and angles, atomic coordinates, and thermal
parameters for 3, 6, 7a , and 7b (32 pages). Ordering informa-
tion is given on any current masthead page.
3.55. For 7b: IR (KBr pellet) νOTf 1271 cm-1, νCdN 1606 cm-1
,
νCO 2030 cm-1 31P NMR (CDCl3) δ -12.5; 1H NMR (CDCl3) δ
;
1.08 (6H, t, J H-H ) 7.3 Hz, CH3 (Et)), 2.19 (2H, d, J H-H ) 10.0
Hz, Hanti), 2.59 (2H, dd, J H-H ) 10.0 Hz, J H-P ) 5.3 Hz, Hsyn),
3.36 (4H, tq, J H-H ) 7.3 Hz, J H-P ) 16.0 Hz, CH2 (Et)), 7.3-
7.5 (30H, m, phenyl); 13C NMR (CDCl3) δ 11.5 (s, CH3 (Et)),
16.4 (d, J P-C ) 58.6 Hz, Ct), 45.5 (s, CH2CH3), 128-134
(phenyl), 163.2 (t, J P-C ) 8.2 Hz, CO), 182.7 (s, Cc).
OM960261A
(15) International Tables for X-ray Crystallography; Kynoch Press:
Birmingham, U.K., 1974; Vol. IV.
(16) NRC VAX: Gabe, E. J .; LePage, Y.; Charland, J .-P.; Lee, F. L.;
White, P. S. J . Appl. Crystallogr. 1989, 22, 384.