Alkoxylation and amination of ring-methyl group in pentamethylcyclopentadienyliridium complexes

Article abstract of DOI:10.1021/om000718n

Reactions of a unidentate bis(diphenylphosphino)methane (dppm) complex Cp*IrCl₂(η¹-dppm) (1) with 2 equiv of NaOR (R = Et, Me, or ⁱPr) give ring-methyl-alkoxylated complexes (C₅Me₄CH₂OR)Ir(η²-dppm) [R = Et (5a); R = Me (5b); R = ⁱPr (5c)], respectively. Cationic complexes [Cp*IrCl(η²-dppm)]OTf (2), [Cp*IrCl{P(OPh)₃}₂]OTf (3), and [Cp*IrCl(PPh₃)₂]OTf (4) react with 2 equiv of NaOEt to give (C₅Me₄CH₂OEt)IrL₂ [L₂ = dppm (5a); L = P(OPh)₃ (6a); L = PPh₃ (7a)], respectively. The complex 3 reacts with 2 equiv of NaO^tBu in ethanol, methanol, 2-propanol, allyl alcohol, or propargyl alcohol to give (C₅Me₄CH₂OR)Ir{P(OPh)₃}₂ [R = Et (6a); R = Me (6b); R = ⁱPr (6c); R = allyl (6d); R = propargyl (6e)], respectively. Furthermore, treatment of 3 with 2 equiv of ⁿBuLi and excess diethylamine, propylamine, N-methylaniline, or aniline in triethylamine as solvent gives ring-methyl aminated complexes (C₅Me₄CH₂NR¹R²)Ir{P(OPh)₃}₂ [R¹ = R² = Et (8a); R¹ = ⁿPr, R² = H (8b); R¹ = Ph, R² = Me (8c); R¹ = Ph, R² = H (8d)], respectively. The structure of 8a has been confirmed by X-ray analysis.

Full text of DOI:10.1021/om000718n

100
Organometallics 2001, 20, 100-105
Alk oxyla tion a n d Am in a tion of Rin g-Meth yl Gr ou p in
P en ta m eth ylcyclop en ta d ien ylir id iu m Com p lexes
Ken-ichi Fujita,* Masashi Nakamura, and Ryohei Yamaguchi*
Department of Natural and Environmental Sciences, Faculty of Integrated Human Studies,
and Graduate School of Human and Environmental Studies, Kyoto University,
Kyoto 606-8501, J apan
Received August 16, 2000
Reactions of a unidentate bis(diphenylphosphino)methane (dppm) complex Cp*IrCl2(η1-
i
dppm) (1) with 2 equiv of NaOR (R ) Et, Me, or Pr) give ring-methyl-alkoxylated complexes
i
(C5Me4CH2OR)Ir(η2-dppm) [R ) Et (5a ); R ) Me (5b); R ) Pr (5c)], respectively. Cationic
complexes [Cp*IrCl(η2-dppm)]OTf (2), [Cp*IrCl{P(OPh)3}2]OTf (3), and [Cp*IrCl(PPh3)2]OTf
(4) react with 2 equiv of NaOEt to give (C5Me4CH2OEt)IrL2 [L2 ) dppm (5a ); L ) P(OPh)3
(6a ); L ) PPh3 (7a )], respectively. The complex 3 reacts with 2 equiv of NaOtBu in ethanol,
methanol, 2-propanol, allyl alcohol, or propargyl alcohol to give (C5Me4CH2OR)Ir{P(OPh)3}2
i
[R ) Et (6a ); R ) Me (6b); R ) Pr (6c); R ) allyl (6d ); R ) propargyl (6e)], respectively.
n
Furthermore, treatment of 3 with 2 equiv of BuLi and excess diethylamine, propylamine,
N-methylaniline, or aniline in triethylamine as solvent gives ring-methyl aminated complexes
(C5Me4CH2NR1R2)Ir{P(OPh)3}2 [R1 ) R2 ) Et (8a ); R1 ) nPr, R2 ) H (8b); R1 ) Ph, R2 ) Me
(8c); R1 ) Ph, R2 ) H (8d )], respectively. The structure of 8a has been confirmed by X-ray
analysis.
In tr od u ction
due to electronic and steric effects. There have been
variety of methods of synthesizing metal complexes with
functionalized cyclopentadienyl ligands C5H4R.2 On the
contrary, relatively few methods of preparing metal
complexes with the permethylcyclopentadienyl analogue
C5Me4CH2R have been known. The reaction of perm-
ethylcyclopentadiene bearing the functional group with
appropriate metal salt is one of the ways to synthesize
a metal complex with a functionalized cyclopentadienyl
ligand.3 However, such reactions suffer the severe
limitation of the functional groups to be introduced. On
the other hand, functionalization of a metal permeth-
ylcyclopentadienyl complex is another way.4,5 Maitlis
and co-workers have reported ring-methyl activations
and functionalizations of Cp* complexes of iridium,4a-c
rhodium,4c and ruthenium.4d-h They have revealed that
the functionalizations of the ring-methyl group of iri-
dium and rhodium complexes proceed in an electrophilic
manner. In this paper we wish to report the first
example of the direct alkoxylation and amination of the
ring-methyl group in Cp*Ir complexes, which proceed
in a nucleophilic manner.6
The cyclopentadienyl (Cp) and pentamethylcyclopen-
tadienyl (Cp*) groups are widely used as ligands in
organometallic chemistry,1 since they form inert bonds
to metals and stabilize metal complexes in both high
and low oxidation states. Recently, much attention has
been paid to functionalized cyclopentadienyl or perm-
ethylcyclopentadienyl ligands C5H4R2 or C5Me4CH2R3-6
because the chemical properties of the organometallic
complex with those ligands often change dramatically
(1) (a) Comprehensive Organometallic Chemistry; Wilkinson, G.,
Stone, F. G. A., Abel, E. W., Eds.; Pergamon Press: Oxford, 1982. (b)
Comprehensive Organometallic Chemistry II; Abel, E. W., Stone, F.
G. A., Wilkinson, G., Atwood, J . D., Eds.; Pergamon Press: Oxford,
1995. (c) Maitlis, P. M. Acc. Chem. Res. 1978, 11, 301.
(2) Coville, N. J .; du Plooy, K. E.; Pickl, W. Coord. Chem. Rev. 1992,
116, 1.
(3) (a) Okuda, J .; Zimmermann, K. H. Chem. Ber. 1989, 122, 1645.
(b) J utzi, P.; Kristen, M. O.; Dahlhaus, J .; Neumann, B.; Stammler,
H.-G. Organometallics 1993, 12, 2980. (c) Adams, H.; Bailey, N. A.;
Colley, M.; Schofield, P. A.; White, C. J . Chem. Soc., Dalton Trans.
1994, 1445.
(4) (a) Miguel-Garcia, J . A.; Adams, H.; Bailey, N. A.; Maitlis, P. M.
J . Organomet. Chem. 1991, 413, 427. (b) Miguel-Garcia, J . A.; Adams,
H.; Bailey, N. A.; Maitlis, P. M. J . Chem. Soc., Dalton Trans. 1992,
131. (c) Gusev, O. V.; Sergeev, S.; Saez, I. M.; Maitlis, P. M.
Organometallics 1994, 13, 2059. (d) Fan, L.; Turner, M. L.; Adams,
H.; Bailey, N. A.; Maitlis, P. M. Organometallics 1995, 14, 676. (e) Fan,
L.; Wei, C.; Aigbirhio, F. I.; Turner, M. L.; Gusev, O. V.; Morozova, L.
N.; Knowles, D. R. T.; Maitlis, P. M. Organometallics 1996, 15, 98. (f)
Gusev, O. V.; Morozova, L. N.; O’Leary, S. R.; Adams, H.; Bailey, N.
A.; Maitlis, P. M. J . Chem. Soc., Dalton Trans. 1996, 2571. (g) Gusev,
O. V.; Morozova, L. N.; Peganova, T. A.; Antipin, M. Y.; Lyssenko, K.
A.; Noels, A. F.; O’Leary, S. R.; Maitlis, P. M. J . Organomet. Chem.
1997, 536-7, 191. (h) Knowles, D. R. T.; Adams, H.; Maitlis, P. M.
Organometallics 1998, 17, 1741.
(5) (a) Ko¨lle, U.; Grub, J . J . Organomet. Chem. 1985, 289, 133. (b)
Gloaguen, B.; Astruc, D. J . Am. Chem. Soc. 1990, 112, 4607. (c) Klahn,
A. H.; Oelckers, B.; Godoy, F.; Garland, M. T.; Vega, A.; Perutz, R. N.;
Higgitt, C. L. J . Chem. Soc., Dalton Trans. 1998, 3079.
(6) A part of this paper has been reported in a preliminary form.
Fujita, K.; Yamaguchi, R. Chem. Lett. 1999, 707.
Resu lts a n d Discu ssion
Alk oxyla tion of th e Rin g-Meth yl Gr ou p in Cp *Ir
Com p lexes. F or m a tion of (C5Me4CH2OR)Ir L2 [R )
Et, L2 ) d p p m (5a ); R ) Me, L2 ) d p p m (5b); R )
iP r , L2 ) d p p m (5c); R ) Et, L ) P (OP h )3 (6a ); R )
Me, L ) P (OP h )3 (6b); R ) iP r , L ) P (OP h )3 (6c); R
) a llyl, L ) P (OP h )3 (6d ); R ) p r op a r gyl, L )
P (OP h )3 (6e); R ) Et, L ) P P h 3 (7a )]. Treatment of
Cp*IrCl2(η1-dppm) (1) with 2 equiv of sodium ethoxide
at room temperature in ethanol afforded a ring-methyl-
alkoxylated complex (C5Me4CH2OEt)Ir(η2-dppm) (5a ) as
1
a yellow powder in 82% yield (eq 1). The H and 13C-
10.1021/om000718n CCC: $20.00 © 2001 American Chemical Society
Publication on Web 12/06/2000

Pentamethylcyclopentadienyliridium Complexes
Ta ble 1. 1H NMR Da ta for Com p lexes 5-8a
Ph
Organometallics, Vol. 20, No. 1, 2001 101
complex
C5Me4
CH2E
E
other signal
5a
2.15 (6H), 2.29 (6H)b 4.60
OEt, 1.20 (t, J ) 6, 3H), 3.50 (q, 7.09-7.23, 7.73-7.77 (20H) 4.32 (t, J ) 11, 2H, PCH2P)
J ) 6, 2H)
5b
5c
2.06 (6H), 2.21 (6H)b 4.49
2.07 (6H), 2.22 (6H)b 4.45
OMe, 3.21 (s, 3H)
7.02-7.15, 7.65-7.69 (20H) 4.24 (t, J ) 11, 2H, PCH2P)
7.01-7.13, 7.66-7.70 (20H) 4.25 (t, J ) 11, 2H, PCH2P)
OiPr, 1.12 (d, J ) 6, 6H), 3.56
(m, 1H)
6a
1.61 (6H), 1.88 (6H)c
3.61
OEt, 1.10 (t, J ) 7, 3H), 3.30
6.86-7.28 (30H)
(q, J ) 7, 2H)
6b
6c
1.60 (6H), 1.87 (6H)
1.61 (6H), 1.86 (6H)
3.53
3.55
OMe, 3.09 (s, 3H)
6.86-7.25 (30H)
6.86-7.26 (30H)
OiPr, 1.09 (d, J ) 6, 6H), 3.41
(m, 1H)
6d
1.60 (6H), 1.87 (6H)
3.62
OAllyl, 3.82 (dt, J ) 5, 2, 2H),
5.04 (ddt, J ) 10, 2, 2, 1H), 5.24
(ddt, J ) 17, 2, 2, 1H), 5.85
(ddt, J ) 17, 10, 5, 1H)
OPropargyl, 2.06 (t, J ) 2, 1H),
3.83 (d, J ) 2, 2H)
6.86-7.25 (30H)
6e
7a
8a
8b
1.58 (6H), 1.88 (6H)
1.58 (6H), 1.61 (6H)
1.67 (6H), 1.93 (6H)
1.66 (6H), 1.83 (6H)
3.67
3.98
2.81
3.01
6.86-7.25 (30H)
OEt, 1.09 (t, J ) 7, 3H), 3.35
(q, J ) 7, 2H)
6.91-7.03, 7.69-7.76 (30H)
6.86-7.28 (30H)
NEt2, 0.92 (t, J ) 7, 6H), 2.34
(q, J ) 7, 4H)
NHnPr, 0.82 (t, J ) 7, 3H), 1.36
(m, 2H), 2.40 (t, J ) 7, 2H)
NMePh, 2.39 (s, 3H, NMe)
NHPh, 3.14 (t, J ) 5, 1H, NH)
6.85-7.28 (30H)
8c
8d
1.66 (6H), 1.78 (6H)
1.70 (6H), 1.78 (6H)
3.72
6.76-7.32 (35H)
6.46-7.27 (35H)
3.42d
a
b
c
d
Measured in C6D6; coupling constants in hertz. Triplet, J ) 2 Hz. Triplet, J ) 3 Hz. Doublet, J ) 5 Hz.
Ta ble 2. 13C{1H} NMR Da ta for Com p lexes 5-8a
complex
C5Me4
CH2E
65.2
E
dppm, P(OPh)3 or PPh3
other signal
5a
11.46, 11.49, 90.0, 90.4, 91.3
OEt, 15.7, 64.9
127.8 (t, J ) 4), 128.8, 131.9
(t, J ) 6), 139.1 (t, J ) 23)
127.8 (t, J ) 5), 128.8, 131.9
(t, J ) 6), 139.1 (t, J ) 22)
127.8 (t, J ) 5), 128.8, 131.9
(t, J ) 5), 139.2 (t, J ) 22)
121.8, 123.5, 129.5, 153.2
121.7, 123.5, 129.5, 153.2
56.7 (t, J ) 31, PCH2P)
5b
5c
11.45, 11.48, 90.06, 90.07, 91.4
67.0
62.8
OMe, 57.1
56.7 (t, J ) 30, PCH2P)
56.7 (t, J ) 30, PCH2P)
11.4, 11.5, 90.1 (t, J ) 4), 90.4,
91.2
10.0, 10.1, 94.7, 95.3, 97.1
10.0, 10.1, 94.4, 95.3 (t, J ) 6),
97.2
10.0, 94.8, 95.1 (t, J ) 6), 97.0
10.0, 10.1, 94.3, 95.3 (t, J ) 5),
97.2
OiPr, 70.1, 22.5
6a
6b
63.6
65.6
OEt, 15.6, 65.4
OMe, 57.6
6c
6d
61.3
63.4
OiPr, 22.5, 70.7
OAllyl, 71.1, 116.0,
135.9
121.8, 123.5, 129.4, 153.2
121.7, 123.5, 129.7, 153.2
6e
7a
8a
10.0, 93.6, 95.4 (t, J ) 6), 97.4
62.9
64.6
48.5
OPropargyl, 57.0, 74.1,
81.1
OEt, 15.7, 65.5
121.7, 123.6, 129.5, 153.2
10.2, 10.6, 92.3, 93.8 (t, J ) 3),
95.3
10.2, 10.8, 95.5 (t, J ) 5), 96.3,
96.9
10.2, 94.5, 96.2, 97.3
10.2, 10.7, 95.2, 95.3 (t, J ) 6),
96.9
126.7 (t, J ) 4), 128.2, 135.3
(t, J ) 6), 139.5 (t, J ) 24)
121.8, 123.5, 129.4, 153.3
NEt2, 12.1, 46.3
8b
8c
44.4
46.7
NHnPr, 11.9, 23.5, 51.9
NMePh, 35.0, 114.6,
117.7, 129.3, 151.2
NHPh, 113.1, 117.4,
129.4, 148.9
121.7, 123.5, 129.5, 153.3
121.7, 123.6, 129.5, 153.2
8d
10.0, 10.1, 94.8 (t, J ) 6), 96.1,
96.6
39.1
121.7, 123.7. 129.5, 153.2
a
Measured in C6D6; coupling constants in hertz.
{1H} NMR data of 5a are summarized in Tables 1 and
2. The H NMR spectrum of 5a showed two signals for
tively (eq 1). NMR signal patterns of 5b and 5c were
similar to that of 5a except for the alkoxy group.
1
the different types of ring-methyl groups (δ 2.29 and
2.15) and one signal for the substituted methylene (δ
4.60). Signals for the methylene protons of dppm were
observed at δ 4.32 as a triplet, indicating that these
protons are equivalent. The 13C{1H} NMR spectrum of
5a showed three signals for C5Me4 (δ 91.3, 90.4, and
90.0), two signals for C5Me4 (δ 11.49 and 11.46), and a
signal for C5Me4CH2 (δ 65.2). In the 31P{1H} NMR
spectrum, one singlet at δ -50.6 was observed, indicat-
ing that two phosphorus are equivalent and the dppm
is η2 bonded. Considering these NMR data, it was
revealed that alkoxylation of one of the ring-methyl
groups in 1 occurred. Similar reactions of 1 with 2 equiv
of sodium methoxide or sodium isopropoxide also gave
ring-methyl alkoxylated complexes 5b and 5c, respec-
We next tried the reactions of cationic complexes
[Cp*IrCl(η2-dppm)]+ (2), [Cp*IrCl{P(OPh)3}2]+ (3), and
[Cp*IrCl(PPh3)2]+ (4) with sodium ethoxide. Treatment
of 2-4 with 2 equiv of sodium ethoxide at room
temperature in ethanol gave ring-methyl-alkoxylated

102 Organometallics, Vol. 20, No. 1, 2001
Fujita et al.
complexes (C5Me4OEt)IrL2 [L2 ) dppm (5a), L ) P(OPh)3
1
(6a ), L ) PPh3 (7a )] (eq 2). The H and 13C{1H} NMR
data of the products are summarized in Tables 1 and 2.
X-r a y Cr ysta l Str u ctu r e of 8a . The structure of 8a
was confirmed by an X-ray diffractional study. The
molecular geometry and atom-numbering system of 8a
are shown in Figure 1, and Tables 3 and 4 summarize
the results obtained. The iridium atom is five site
coordinated if the η5-C5Me4CH2NEt2 group is considered
as filling three coordination sites. The iridium atom
would be formally in the oxidation state +I. Two
triphenyl phosphite ligands coordinate to the iridium
center with a P(1)-Ir(1)-P(2) angle of 90.9(1)°. The
diethylamino moiety is located above the C5 ring and
opposite the iridium center, indicating that there are
no interaction between iridium and nitrogen. The C5
ring is nonsymmetrically η5-bonded, with C(1) slightly
closer to the iridium center [2.233(9) Å] than C(2)-C(5)
[2.27(1)-2.30(1) Å].
We have also found that present ring-methyl alkoxy-
lations can be generally achieved when the reactions
are carried out using sodium tert-butoxide in appropri-
ate alcohol as solvent. Thus, the cationic complex 3
reacted with 2 equiv of sodium tert-butoxide at room
temperature in ethanol, methanol, 2-propanol, allyl
alcohol, or propargyl alcohol to give the corresponding
alkoxy complexes, (C5Me4CH2OR)Ir{P(OPh)3}2 [R ) Et
i
(6a ); R ) Me (6b); R ) Pr (6c); R ) allyl (6d ); R )
propargyl (6e)] in good yield, respectively (eq 3). The
1H and 13C{1H} NMR data of the products are sum-
1
marized in Tables 1 and 2. In the H NMR spectrum of
6d olefinic protons were observed at δ 5.85, 5.24, and
5.04, indicating no coordination of the allyl moiety to
the iridium center.
Mech a n ism for th e Alk oxyla tion a n d Am in a tion
of th e Rin g-Meth yl Gr ou p in th e Cp *Ir Com p lex.
A possible mechanism for the alkoxylation and amina-
tion reaction is shown in Scheme 1. In the reaction of
neutral complex 1, coordination of the dangling phos-
phine moiety to the iridium center would occur at first.
Base-promoted deprotonation from the ring-methyl in
the cationic Cp* complex could take place to afford a
η4-tetramethylfulvene intermediate A.8 It has been
reported that η4-tetramethylfulvene complexes react
with electrophiles to afford substituted permethylcyclo-
pentadienyl complexes.4c On the other hand, it has also
been reported that η6-tetramethylfulvene complexes
react with nucleophiles.4d,5a,c Considering these facts,
in the present reactions the intermediate A would
transform into a cationic η6-tetramethylfulvene inter-
mediate A′, which could be subjected to nucleophilic
addition of alkoxide or amide anion to the methylidene
moiety. However, we cannot rule out the other route via
a chloride-migrated intermediate B, from which the
product could be afforded by nucleophilic substitution.
To isolate the plausible intermediate A, A′, or B, the
reaction of 3 with 1 equiv of NaOtBu in ethanol was
attempted, which resulted in formation of 5a in low
yield in addition to the recovery of starting complex 3.
Am in a tion of th e Rin g-Meth yl Gr ou p in th e
Cp *Ir Com p lex. F or m a tion of (C5Me4CH2NR1R2)-
n
Ir {P (OP h )3}2 [R1 ) R2 ) Et (8a ); R1 ) P r , R2 ) H
(8b); R1 ) P h , R2 ) Me (8c); R1 ) P h , R2 ) H (8d )].
The complex 3 reacted with 2 equiv of nBuLi in the
presence of excess diethylamine in triethylamine as
solvent to give the ring-methyl-aminated complex (C5-
Me4CH2NEt2)Ir{P(OPh)3}2 (8a ) as a yellow powder in
78% yield (eq 4). The complex 8a was also obtained in
a reasonable yield when the reaction was carried out
using diethylamine as solvent. However, no ring-methyl-
aminated complex was afforded when tetrahydrofuran
was used as solvent. Reactions of 3 with nBuLi in the
presence of propylamine, N-methylaniline, or aniline in
triethylamine also gave aminated complexes (C5Me4-
Su m m a r y
In this paper we have reported the direct alkoxylation
and amination of the ring-methyl group in Cp*Ir
complexes. The present results indicate that a wide
variety of alkoxylation of Cp*Ir complexes could be
achieved in a facile manner by use of NaOtBu in various
alcohols as solvent. The amination reactions reported
here are, to the best of our knowledge, the first examples
n
CH2NR1R2)Ir{P(OPh)3}2 [R1 ) Pr, R2 ) H (8b); R1 )
Ph, R2 ) Me (8c); R1 ) Ph, R2 ) H (8d )], respectively
(eq 4). These reactions are, to the best of our knowledge,
the first example of direct amination of a ring-methyl
group in pentamethylcyclopentadienylmetal complexes.7
1H and 13C{1H} NMR data of 8a -d are summarized in
Tables 1 and 2. NMR signal patterns for the C5Me4
moiety in 8a -d were similar to those of alkoxylated
complexes.
(7) Maitlis, P. M. et al. have reported the synthesis of amino-
substituted permethylcyclopentadienylruthenium complexes derived
from chloro-substituted complexes.4d

Pentamethylcyclopentadienyliridium Complexes
Organometallics, Vol. 20, No. 1, 2001 103
Ta ble 4. Selected Bon d Len gth s a n d An gles for
(C5Me4CH2NEt2)Ir {P (OP h )3}2 (8a )
Bond Lengths (Å)
Ir(1)-P(1)
Ir(1)-C(1)
Ir(1)-C(3)
Ir(1)-C(5)
C(1)-C(5)
C(2)-C(3)
C(4)-C(5)
2.141(3)
2.233(9)
2.30(1)
2.30(1)
1.39(1)
1.38(2)
1.37(2)
Ir(1)-P(2)
Ir(1)-C(2)
Ir(1)-C(4)
C(1)-C(2)
C(1)-C(6)
C(3)-C(4)
C(6)-N(1)
2.156(3)
2.29(1)
2.27(1)
1.45(1)
1.50(1)
1.48(2)
1.42(1)
Bond Angles (deg)
P(1)-Ir(1)-P(2)
90.9(1)
C(1)-C(6)-N(1)
113.3(9)
Sch em e 1
F igu r e 1. ORTEP view of 8a .
Ta ble 3. Cr ysta l Da ta a n d Str u ctu r e Refin em en t
P a r a m eter s for (C5Me4CH2NEt2)Ir {P (OP h )3}2 (8a )
Description of Crystal
color
yellow
habit
plate
max cryst dimens (mm)
0.50 × 0.30 × 0.10
trigonal
R3h
43.11(3)
13.14(1)
21145(17)
18
cryst syst
space group
a (Å)
c (Å)
V (Å3)
Z
formula
fw
D
C50H54NO6P2Ir
1019.15
1.440
calc (g cm-3
)
Data Collection
radiation (λ, Å)
scan technique
scan width (deg)
2θmax (deg)
Mo KR (0.71069)
ω-2θ
standard procedures and distilled prior to use. The complexes
[Cp*IrCl2]2
literature methods. Other reagents were used as obtained from
commercial sources.
(1.00 + 0.30 tan θ)
50.0
and Cp*IrCl2(η1-dppm) (1)9c were prepared by
9a,b
no. of rflns measd
6403
Structure Determination
no. of rflns used
Syn th esis of [Cp *Ir Cl(η2-d p p m )]OTf (2). To a mixture
of Cp*IrCl2(η1-dppm) (1) (0.277 g, 0.354 mmol) and silver
trifluoromethanesulfonate (0.102 g, 0.399 mmol) was added
tetrahydrofuran (10 mL), and the mixture was stirred for 4.5
h. The color of the solution changed to pale yellow accompanied
by precipitation of white powder (AgCl). After filtration,
evaporation of the solvent, followed by washing with hexane
(25 mL) gave 1 as a pale yellow powder (0.139 g, 0.155 mmol,
4593 (I > 1.00σ(I))
541
8.49
0.63-1.00
1.73
0.051
0.050
0.030
no. of params varied
data/param ratio
transmn factors
goodness of fit
Ra
a
Rw
p factor
a
2
R ) ∑||Fo| - |Fc||/∑|Fo|, Rw ) [∑w(|Fo| - |Fc|)2/∑wFo
]
1/2. w )
1
44%). Mp: 262.1 °C (dec). H NMR (CDCl3): δ 1.79 (t, J ) 2
[σ2(Fo) + p2(Fo)2/4]-1
.
Hz, 15H, C5Me5), 4.63 (td, J HP ) 13 Hz, J HH ) 16 Hz, 1H,
PCHHP), 6.30 (td, J HP ) 10 Hz, J HH ) 16 Hz, 1H, PCHHP),
7.23-7.58 (m, 20H, Ph). 13C{1H} NMR (CDCl3): δ 9.3 (s,
C5Me5), 45.3 (t, J ) 33 Hz, PCH2P), 98.2 (s, C5Me5), 126.8 (t,
J ) 33 Hz, Ph), 127.2 (t, J ) 27 Hz, Ph), 128.9 (t, J ) 6 Hz,
Ph), 129.2 (t, J ) 5 Hz, Ph), 131.9 (s, Ph), 132.3 (t, J ) 5 Hz,
Ph), 132.4 (t, J ) 5 Hz, Ph), 132.6 (s, Ph). 31P{1H} NMR
(CDCl3): δ -37.8. Anal. Calcd for C36H37ClF3O3P2SIr: C, 48.24;
H, 4.16; Cl, 3.96. Found: C, 48.23; H, 4.03; Cl, 3.93.
of direct aminations of the ring-methyl group in Cp*
metal complexes. Investigation of the reactivities of
functionalized permethylcyclopentadienyl complexes is
now in progress.
Exp er im en ta l Section
All manipulations were performed under
a dry argon
atmosphere with standard Schlenk techniques. Melting points
were determined on a Yanagimoto micro melting point ap-
paratus. Elemental analyses were carried out at the Mi-
croanalysis Center of Kyoto University. Infrared spectra were
taken on a HORIBA FT-300 spectrometer. 1H, 13C{1H}, and
31P{1H} spectra were measured with J EOL EX-270 and
J EOL A-500 spectrometers. Solvents were dried by using
(8) Formation of a tetramethylfulvene iridium complex by the
reaction of a Cp* complex with base has been reported. Glueck, D. S.;
Bergman, R. G. Organometallics 1990, 9, 2862, and ref 4c.
(9) (a) Kang, J . W.; Moseley, K.; Maitlis, P. M. J . Am. Chem. Soc.
1969, 91, 5970. (b) Ball, R. G.; Graham, W. A. G.; Heinekey, D. M.;
Hoyano, J . K.; McMaster, A. D.; Mattson B. M.; Michel S. T. Inorg.
Chem. 1990, 29, 2023. (c) Valderrama, M.; Contreras, R. J . Organomet.
Chem. 1996, 513, 7.

104 Organometallics, Vol. 20, No. 1, 2001
Fujita et al.
Syn th esis of [Cp *Ir Cl{P (OP h )3}2]OTf (3). To a solution
of [Cp*IrCl2]2 (0.930 g, 1.17 mmol) in chloroform (23 mL) was
added triphenyl phosphite (1.35 mL, 1.60 g, 5.16 mmol), and
the mixture was stirred for 1 h. Then silver trifluoromethane-
sulfonate (0.641 g, 2.50 mmol) was added. The mixture was
stirred for 16 h. The color of the solution changed from orange
to yellow accompanied by precipitation of a white powder
(AgCl). After filteration, evaporation of the solvent followed
by washing with hexane (70 mL) gave 3 as a pale yellow
powder (2.44 g, 2.15 mmol, 92%). Mp: 129.5 °C (dec). 1H NMR
(CDCl3): δ 1.70 (t, J ) 4 Hz, 15H, C5Me5), 7.05-7.23 (m, 30H,
Ph). 13C{1H} NMR (CDCl3): δ 9.2 (C5Me5), 104.3 (C5Me5), 120.5
(Ph), 125.9 (Ph), 129.9 (Ph), 150.9 (t, J ) 7 Hz, Ph). 31P{1H}
NMR (CDCl3): δ 59.6. Anal. Calcd for C47H45ClF3O9P2SIr: C,
49.84; H, 4.00; Cl, 3.13. Found: C, 49.87; H, 3.89; Cl, 3.00.
Syn th esis of [Cp *Ir Cl(P P h 3)2]OTf (4). To a mixture of
[Cp*IrCl2]2 (0.468 g, 0.588 mmol) and PPh3 (0.620 g, 2.36
mmol) was added chloroform (18 mL), and the mixture was
stirred for 4 h. Then silver trifluoromethanesulfonate (0.307
g, 1.20 mmol) was added. The mixture was stirred for 15 h.
The color of the solution changed from orange to yellow
accompanied by precipitation of a white powder (AgCl). After
filtration, evaporation of the solvent followed by washing with
hexane (35 mL) gave 4 as a yellow powder (1.12 g, 1.08
mmol, 92%). Mp: 235.7-237.2 °C. 1H NMR (CDCl3): δ 1.14
(s, C5Me5), 7.10-7.48 (br, Ph). 13C{1H} NMR (CDCl3): δ 8.8
(C5Me5), 101.6 (C5Me5), 128.0 (Ph), 131.1 (Ph), 134.7 (Ph).
temperature, and the mixture was stirred for 1 h. After
removal of volatiles, the residue was extracted with diethyl
ether (7 mL). Evaporation of solvent gave 6a as a pale yellow
powder (0.0883 g, 0.0890 mmol, 88%).
Similar reaction of 3 (0.114 g, 0.101 mmol) and NaOtBu
(0.0196 g, 0.204 mmol) in methanol gave 6b as a pale yel-
low powder (0.0829 g, 0.0848 mmol, 84%). Mp: 86.4 °C (dec).
31P{1H} NMR (C6D6): δ 78.4. Anal. Calcd for C47H47O7P2Ir: C,
57.72; H, 4.84. Found: C, 57.71; H, 4.87.
Similar reaction of 3 (0.108 g, 0.0951 mmol) and NaOtBu
(0.0183 g, 0.190 mmol) in 2-propanol gave 6c as a pale yel-
low powder (0.0681 g, 0.0677 mmol, 71%). Mp: 87.9 °C (dec).
31P{1H} NMR (C6D6): δ 78.6. Anal. Calcd for C49H51O7P2Ir: C,
58.50; H, 5.11. Found: C, 58.23; H, 4.92.
Similar reaction of 3 (0.0746 g, 0.0659 mmol) and NaOtBu
(0.0128 g, 0.133 mmol) in allyl alcohol gave 6d as a pale yel-
low powder (0.0618 g, 0.0615 mmol, 93%). Mp: 126.5 °C (dec).
31P{1H} NMR (C6D6): δ 78.4. Anal. Calcd for C49H49O7P2Ir: C,
58.61; H, 4.92. Found: C, 58.79; H, 4.88.
Similar reaction of 3 (0.0665 g, 0.0587 mmol) and NaOtBu
(0.0105 g, 0.109 mmol) in propargyl alcohol gave 6e as a pale
yellow powder (0.0511 g, 0.0510 mmol, 87%). Mp: 139.2 °C
(dec). 31P{1H} NMR (C6D6): δ 78.4. Anal. Calcd for C49H47O7P2-
Ir: C, 58.73; H, 4.73. Found: C, 58.66; H, 4.78.
Syn th esis of (C5Me4CH2NR1R2)Ir {P (OP h )3}2 [R1 ) R2
) Et (8a ); R1 ) n P r , R2 ) H (8b); R1 ) P h , R2 ) Me (8c); R1
) P h , R2 ) H (8d )]. To a suspension of 3 (0.072 g, 0.064 mmol)
in triethylamine (2 mL) was added diethylamine (17 µL, 0.16
mmol). nBuLi (1.7 M hexane solution, 0.080 mL, 0.14 mmol)
was added at -50 °C. The mixture was slowly warmed to room
temperature and stirred for 2 h. After removal of volatiles,
the residue was extracted with hexane (5 mL). Evaporation
of solvent gave 8a as a yellow powder (0.051 g, 0.050 mmol,
78%). Mp: 127.2 °C (dec). 31P{1H} NMR (C6D6): δ 77.7. Anal.
Calcd for C50H54NO6P2Ir: C, 58.93; H, 5.34; N, 1.37. Found:
C, 58.95; H, 5.39; N, 1.25.
31P{1H} NMR (CDCl3): δ -11.2. Anal. Calcd for C47H45
-
ClF3O3P2SIr: C, 54.46; H, 4.38; Cl, 3.42. Found: C, 53.68; H,
4.58; Cl, 3.33.
Syn th esis of (C5Me4CH2OR)Ir (η2-d p p m ) [R ) Et (5a );
R ) Me (5b); R ) iP r (5c)]. To a mixture of 1 (0.195 g, 0.250
mmol) and NaOEt (0.0372 g, 0.547 mmol) was added ethanol
(10 mL) at room temperature, and the mixture was stirred
for 2.3 h. After removal of volatiles, the residue was extracted
with hexane (8 mL). Evaporation of solvent gave 5a as a yel-
low powder (0.155 g, 0.205 mmol, 82%). Mp: 98.3 °C (dec).
31P{1H} NMR (C6D6): δ -50.6. Anal. Calcd for C37H41OP2Ir:
C, 58.79; H, 5.47. Found: C, 58.53; H, 5.54.
Similar reaction of 3 (0.142 g, 0.126 mmol) with nBuLi (0.26
mmol) in the presence of propylamine (45 µL, 0.55 mmol) gave
8b as a pale yellow powder (0.120 g, 0.119 mmol, 95%). Mp:
93.1 °C (dec). 31P{1H} NMR (C6D6): δ 78.0. Anal. Calcd for
C49H52NO6P2Ir: C, 58.55; H, 5.21; N, 1.39. Found: C, 58.82;
H, 5.21; N, 1.24.
Similar reaction of 1 (0.0963 g, 0.123 mmol) and NaOMe
(0.0133 g, 0.246 mmol) in methanol gave a pale yellow powder,
5b (0.0160 g, 0.0216 mmol, 18%). The yield of 5b was low (18%)
because of its instability. Mp: 87.3 °C (dec). 31P{1H} NMR
(C6D6): δ -50.6. Anal. Calcd for C36H39OP2Ir: C, 58.28; H,
5.30. Found: C, 57.78; H, 5.33.
Similar reaction of 1 (0.0617 g, 0.0788 mmol) and NaOiPr
(0.0118 g, 0.144 mmol) in 2-propanol gave a pale yellow
powder, 5c (0.0263 g, 0.0342 mmol, 43%). Mp: 103.0 °C (dec).
31P{1H} NMR (C6D6): δ -50.7. Anal. Calcd for C36H39OP2Ir:
C, 59.28; H, 5.63. Found: C, 59.36; H, 5.45.
Syn th esis of (C5Me4CH2OEt)Ir L2 [L2 ) d p p m (5a ); L )
P (OP h )3 (6a ); L ) P P h 3 (7a )]. To a mixture of 2 (0.050 g,
0.056 mmol) and NaOEt (0.0095 g, 0.14 mmol) was added
ethanol (4 mL) at room temperature, and the mixture was
stirred for 10 min. After removal of volatiles, the residue was
extracted with hexane (7 mL). Evaporation of solvent gave a
yellow powder, 5a (0.033 g, 0.044 mmol, 78%).
Similar reaction of 3 (0.0863 g, 0.0762 mmol) and NaOEt
(0.0173 g, 0.254 mmol) in ethanol gave a pale yellow powder,
6a (0.0428 g, 0.0431 mmol, 57%). Mp: 106.2 °C (dec). 31P{1H}
NMR (C6D6): δ 78.5. Anal. Calcd for C48H49O7P2Ir: C, 58.11;
H, 4.98. Found: C, 58.28; H, 4.77.
n
Similar reaction of 3 (0.102 g, 0.0904 mmol) with BuLi (0.18
mmol) in the presence of N-methylaniline (0.37 mmol) gave
8c as a yellow powder (0.0770 g, 0.0731 mmol, 81%). Mp: 68.1
°C (dec). 31P{1H} NMR (C6D6): δ 77.2. Elemental analysis for
8c was unsatisfactory because of a small amount of contami-
nant.
Similar reaction of 3 (0.50 g, 0.44 mmol) with nBuLi (0.90
mmol) in the presence of aniline (0.89 mmol) gave 8d as a
yellow powder (0.31 g, 0.30 mmol, 68%). Mp: 121.4 °C (dec).
31P{1H} NMR (C6D6): δ 77.2. Anal. Calcd for C52H50NO6P2Ir:
C, 60.10; H, 4.85; N, 1.35. Found: C, 59.37; H, 4.84; N, 1.25.
X-r a y Str u ctu r e An a lysis of 8a . The crystal data and
experimental details for 8a are summarized in Table 3.
Diffraction data were obtained with a Rigaku AFC-5S. The
reflection intensities were monitored by three standard reflec-
tions at every 150 measurements. Decay correction was ap-
plied. Reflection data were corrected for Lorentz and polariza-
tion effects. Absorption corrections were empirically applied.
The structure was solved by the heavy-atom Patterson meth-
ods10,11 and refined anisotropically for non-hydrogen atoms by
full-matrix least-squares calculations. Atomic scattering fac-
Similar reaction of 4 (0.0419 g, 0.0404 mmol) and NaOEt
(0.0150 g, 0.220 mmol) in ethanol gave a red powder, 7a
(0.0284 g, 0.0317 mmol, 78%). Mp: 60.2 °C (dec). 31P{1H} NMR
(C6D6): δ 19.4. Elemental analysis for 7a was unsatisfactory
because of a small amount of contaminant.
(10) PATTY: Beurskens, P. T.; Admiraal, G.; Beurskens, G.; Bos-
man, W. P.; Garcia-Granda, S.; Gould, R. O.; Smits, J . M. M.; Smykalla,
C. Technical Report of the Crystallography Laboratory; University of
Nijmegen, 1992.
(11) DIRDIF94: Beurskens, P. T.; Admiraal, G.; Beurskens, G.;
Bosman, W. P.; de Gelder, R.; Israel, R.; Smits, J . M. M. Technical
Report of the Crystallography Laboratory; University of Nijmegen,
1994.
Syn th esis of (C5Me4CH2OR)Ir {P (OP h )3}2 [R ) Et (6a );
i
R ) Me (6b); R ) P r (6c); R ) a llyl (6d ); R ) p r op a r gyl
(6e)]. To a mixture of 3 (0.115 g, 0.102 mmol) and NaOtBu
(0.0197 g, 0.205 mmol) was added ethanol (6 mL) at room

Pentamethylcyclopentadienyliridium Complexes
Organometallics, Vol. 20, No. 1, 2001 105
tors and anomalous dispersion terms were taken from litera-
ture.12 All hydrogen atoms were not refined; hydrogen atoms
were located on idealized positions. The calculations were
performed using the program system teXsan.13 Selected bond
lengths and angles are summarized in Table 4.
Su p p or tin g In for m a tion Ava ila ble: X-ray structural
data for 8a . This material is available free of charge via the
Internet at http://pubs.acs.org.
(12) (a) Cromer, D. T.; Waber, G. T. International Tables for X-ray
Crystallography; Kynoch: Birmingham, U.K., 1974; Vol. IV. (b) Ibers,
J . A.; Hamilton, W. C. Acta Crystallogr. 1964, 17, 781. (c) Creagh, D.
C.; McAuley, W. J . In International Tables for X-ray Crystallography;
Wilson A. J . C., Ed.; Kluwer Academic Publishers: Boston, MA, 1992;
Vol. C. (d) Creagh, D. C.; Hubbell, J . H. In International Tables for
X-ray Crystallography; Wilson, A. J . C., Ed.; Kluwer Academic
Publishers: Boston, MA, 1992; Vol. C.
OM000718N
(13) teXsan for Windows, Crystal Structure Analysis Package;
Molecular Structure Corp., 1997.