Bis(phosphine) Pd(II)-azido complexes containing heterocyclic ligands: Reactivity toward organic isocyanides

Article abstract of DOI:10.1016/j.ica.2007.10.026

Bis(phosphine) Pd-azido complexes containing heterocycles such as tetrazolyl, pyrazinyl, and thienyl groups reacted with aryl isocyanides to give the corresponding Pd-carbodiimido or -imidoyl carbodiimido complexes. These products were formed by the insertion of the isocyanides into the Pd-N (azido) or the Pd-C (heterocycles) bond.

Full text of DOI:10.1016/j.ica.2007.10.026

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Inorganica Chimica Acta 361 (2008) 2159–2165
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Note
Bis(phosphine) Pd(II)–azido complexes containing heterocyclic
ligands: Reactivity toward organic isocyanides
a,
a
a
b
b
Yong-Joo Kim *, Kyung-Eun Lee , Hyeong-Tak Jeon , Hyun Sue Huh , Soon W. Lee
a
Department of Chemistry, Kangnung National University, Kangnung 210-702, Republic of Korea
Department of Chemistry, Sungkyunkwan University, Natural Science Campus, Suwon 440-746, Republic of Korea
b
Received 13 July 2007; received in revised form 13 October 2007; accepted 21 October 2007
Available online 26 October 2007
Abstract
Bis(phosphine) Pd–azido complexes containing heterocycles such as tetrazolyl, pyrazinyl, and thienyl groups reacted with aryl isocy-
anides to give the corresponding Pd–carbodiimido or –imidoyl carbodiimido complexes. These products were formed by the insertion of
the isocyanides into the Pd–N (azido) or the Pd–C (heterocycles) bond.
ꢀ 2007 Elsevier B.V. All rights reserved.
Keywords: Azido; Carbodiimido; Imidoyl; Tetrazolyl; Thienyl; Palladium
1. Introduction
plexes containing the heterocyclic ligands and their reactiv-
ity toward organic isocyanides.
Unsaturated molecules such as CO and isocyanides
readily insert into palladium–carbon bonds to produce var-
ious organic compounds via palladium-catalyzed reactions
[1–4]. In particular, the isocyanide insertion gives an imi-
doyl compound, an intermediate in catalytic reactions or
a precursor of organic heterocycles in depalladation reac-
tions [5–14].
We have published several papers on the reactivity of
bis(azido) or mono(azido) complexes of group 10 metals
[M(N3)2Ln] or ½MðN3ÞL0nꢀ, in which supporting ligands
are tertiary phosphines or C,N-chelated ligands, toward
organic isocyanides to give the complexes containing a C-
coordinated tetrazolato ring, a carbodiimido group, or a
imidoyl group, depending on the nature of incoming isocy-
anides or coordinated ligands (Scheme 1) [15]. As an exten-
sion of our ongoing research, we set out to study the
aforementioned reactivity for another family of Pd–azido
complexes having heterocyclic ligands. In this paper, we
report the preparation of bis(phosphine) Pd–azido com-
2. Results and discussion
2.1. Preparation of bis(phosphine) Pd(II)–azido complexes
containing heterocyclic ligands
The starting complexes 1–5 [Pd(R)(X)L2] (L = tertiary
phosphines; R = tetrazolyl, thienyl, pyrazinyl, and pyridyl;
X = Cl, Br) were obtained by the oxidative addition of R–
X to [Pd(CH2@CHPh)L2] (L = PMe3 or PMe2Ph) [16,17],
which was generated in situ from trans-[PdEt2L2] and sty-
rene. The subsequent treatments of complexes 1–5 with
excess NaN3 produced the corresponding Pd–azido com-
plexes 6–10 containing heterocyclic ligands in high yields
(Scheme 2).
The IR spectra of complexes 6–10 display a strong N3
stretch at 2032–2055 cmꢁ1. Crystal data of 6 are summa-
rized in Table 1. Fig. 1 shows the molecular structure of
6, which shows a slightly distorted square-planar structure,
consisting of two trans-PMe3 ligands, one tetrazolato
ligand and one azido ligand. The tetrazolate ring is essen-
tially planar and has a dihedral angle of 70.1(2)ꢁ with
*
Corresponding author. Tel.: +82 33 640 2308; fax: +82 33 647 1183.
E-mail address: yjkim@kangnung.ac.kr (Y.-J. Kim).
0020-1693/$ - see front matter ꢀ 2007 Elsevier B.V. All rights reserved.
doi:10.1016/j.ica.2007.10.026

2160
Y.-J. Kim et al. / Inorganica Chimica Acta 361 (2008) 2159–2165
R
N
respect to the equatorial plane. In addition, the dihedral
angle between the tetrazolate and phenyl rings is 37.2(3)ꢁ.
Previously, we reported that the aryl palladium–azido
bis(phosphine) complex [ArPd(N3)(PMe3)2] (Ar = phenyl,
2,6-diphenylpyridine) reacted with organic isocynaides to
give the imidoyl Pd carbodiimido complex [Pd(N@C@N–
Ar0){C(@N–R)Ar}(PMe3)2] [15d]. On the basis of the
above results, we decided to examine the same reactivity
(isocyanide insertion) for palladium–azido complexes con-
taining heterocyclic ligands. Treating the Pd–thienyl com-
plexes 3 and 8 with isocyanide (2,6-dimethylphenyl
N
LnM
N
N
LnM-N3
+ CN-R
R
N
- N2
N
LnM
LnM N=C=N-R
N
N
Scheme 1.
L
Ph
L
R
X
trans-PdEt2L2
( L = PMe3, PMe2Ph)
Pd
R
Pd
L
X
L
Ph
1 ~ 5
NaN3
L
Pd
L
Ar
N
S
N
R
N3
,
,
,
R =
N
N
N
N
N
10
8
9
L = PMe3, 6
L = PMe2Ph, 7
Scheme 2.
Table 1
X-ray data collection and structure refinements for 6, 11, 12 and 14
6
11
12
14
Formula
Fw
C
13H23N7P2Pd
C19H30NP2SBrPd
C28H39N3P2SPd
618.02
295(2)
0.56 · 0.54 · 0.52
triclinic
C32H36N6P2Pd
673.01
295(2)
0.50 · 0.44 · 0.40
orthorhombic
Pca21
11.626(1)
11.701(1)
22.553(2)
445.72
296(2)
0.22 · 0.20 · 0.18
monoclinic
P21/c
6.873(1)
23.602 (5)
11.950 (2)
106.32 (1)
1860.4 (6)
4
1.591
1.178
904
0.5832
0.6202
3514
552.75
295(2)
0.36 · 0.34 · 0.32
monoclinic
P21/n
10.517(2)
11.745(2)
19.755(4)
93.22(2)
2436.3(8)
4
1.507
2.622
1112
0.4700
0.8280
6429
Temperature (K)
Crystal size (mm)
Crystal system
Space group
ꢀ
P1
˚
a (A)
9.107 (1)
13.401(2)
13.823(2)
75.88(1)
1559.9(4)
2
1.316
0.784
640
˚
b (A)
˚
c (A)
b (ꢁ)
3
˚
V (A )
3204.0(6)
4
1.395
0.710
1384
0.3739
0.4409
5585
Z
Dcalc (g cmꢁ3
)
l (mmꢁ1
F(000)
Tmin
)
0.4021
0.7963
5657
Tmax
Number of measured reflections
Number of unique reflections
3231
4239
5345
5585
Number of refections with I > 2r(I)
2450
3275
4980
5276
Number of refined paꢁra3meters
209
0.607
226
1.081
317
0.444
371
˚
Maximum in Dq (e A
)
0.285
ꢁ0.494
1.031
0.0265
0.0691
ꢁ3
˚
Minimum in Dq (e A
)
ꢁ0.820
ꢁ0.675
ꢁ0.421
Goodness-of-fit on F2
1.035
1.030
1.037
Ra
wR2
0.0453
0.0990
0.0398
0.0912
0.0347
0.0983
b
P
P
a
R ¼ ½jF oj ꢁ jF cjꢀ= jF ojꢀ.
P
P
2
2 1=2
b
wR2 ¼ ½wðF 2o ꢁ F c2Þ ꢀ= ½wðF 2oÞ ꢀ
.

Y.-J. Kim et al. / Inorganica Chimica Acta 361 (2008) 2159–2165
2161
˚
Fig. 2. ORTEP drawing of 11. Selected bond lengths (A) and angles (ꢁ):
Pd1–C15 2.027(4), Pd1–P1 2.314(1), Pd1–P2 2.359(1), Pd1–Br1 2.5663(7),
N1–C15 1.294(5), N1–C7 1.411(6), C15–C16 1.477(6); C15–Pd1–P1
91.5(1), C15–Pd1–P2 91.0(1), P1–Pd1–P2 173.11(5), C15–Pd1–Br1
175.5(1), P1–Pd1–Br1 90.38(4), P2–Pd1–Br1 87.54(4), C15–N1–C7
127.5(4), N1–C15–C16 114.7(4), N1–C15–Pd1 129.6(3), C16–C15–Pd1
115.8(3).
Fig. 1. ORTEP drawing [21] of 6 showing the atom-labelling scheme and
50% probability thermal ellipsoids. Selected bond lengths (A) and angles
˚
(ꢁ): Pd1–C7 1.951(6), Pd1–N5 2.040(6), Pd1–P2 2.283(2), Pd1–P1 2.284(2),
N1–C7 1.312(7), N1–N2 1.360(8), N2–N3 1.259(8), N3–N4 1.348(7), N4–
C7 1.344(7), N4–C8 1.398(7), N5–N6 1.133(8), N6–N7 1.145(9); C7–Pd1–
N5 176.1(2), C7–Pd1–P2 91.2(2), N5–Pd1–P2 92.6(2), P2–Pd1–P1
174.1(1), C7–N1–N2 107.3(5), N3–N2–N1 110.9(5), N2–N3–N4
106.2(5), C7–N4–N3 109.7(5), N6–N5–Pd1 132.1(6), N5–N6–N7
176.2(9), N1–C7–N4 105.9(5).
the imidoyl (–C@N(Ar)–) group. Molecular structures of
11and 12 (Figs. 2 and 3) clearly show an imidoyl {–
C@N(Ar)} group, formed by the isocyanide insertion into
the Pd–C bond. In addition, complex 12 has a carbodiim-
ido (–N@C@N–Ar) group (in Fig. 3) trans to the imidoyl
group.
In contrast, the corresponding reactions of the tetrazola-
to or pyrazinyl analogs [R(N3)PdL2] (R = tetrazolyl;
L = PMe3 (6), PMe2Ph (7); R = pyrazinyl, L = PMe3 (9))
with 2 equiv or more organic isocyanides led to the forma-
tion of carbodiimido complexes (13–15) (Scheme 4). No
products resulting from the isocyanide insertion into the
Pd–C (heterocycles) bond were observed.
IR spectra of complexes 13–15 also display a sharp band
at 2106–2138 cmꢁ1 due to the NCN groups of the carbo-
diimido groups. The ORTEP drawing of compound 14 is
shown in Fig. 4, which illustrates a square-planar coordina-
tion sphere of Pd containing two PMe2Ph ligands, one 2,6-
dimethylphenyl carbodiimido ligand and one tetrazolyl
ligand.
CN
PMe3
S
PMe3
Br
Pd
Pd Br
PMe3
3
N
S
S
11
PMe3
2 CN
PMe3
PMe3
Pd
N
C
N
N3
Pd
S
N
PMe3
PMe3
8
12
Scheme 3.
isocyanide) produced an imidoyl Pd complex (11) and an
imidoyl Pd carbodiimide (12), respectively (Scheme 3).
The reactivity depends on the amount of the added isocy-
anide. Whereas compound 11 was formed by the isocya-
nide insertion into the Pd–C bond (1:1 mole ratio),
compound 12 was formed by the isocyanide insertion into
both the Pd–C bond and the Pd–N bonds followed by N2
extrusion (1:2 mole ratio). It should be mentioned that our
group [17] and other groups [8b,18] reported the isocyanide
insertion into palladium or platinum halides containing a
thienyl group to produce the imidoyl halide complexes.
IR spectrum of complex 12 displays a sharp stretch at
2140 cmꢁ1 due to the N@C@N group of the carbodiimido
ligand as well as a strong stretch at 1556 cmꢁ1 assignable to
It has been observed that azido complexes 6 and 7 first
produced
a
mixture of
a
bis(tetrazolyl) complex
[RPdL2{CN4(2,6-Me2C6H3)}] and a mono(carbodiimido)
complex [RPdL2(N@C@N–2,6-Me2C6H3)] (13 and 14) in
the mole ratio of 3:7 at room temperature, and this mixture
subsequently converted to the mono(carbodiimido) com-
plexes when heated at 60 ꢁC. These results are consistent
with our previous observation that bis(azido) bis(phos-
phine) complexes M(N3)2L2 (M = Ni, Pd, Pt; L = PR3)
reacted with organic isocyanides to give the corresponding
bis(carbodiimido)complexes via a bis(tetrazolato) interme-
diate [L2M{CN4(Ar)}2] [15a]. Unexpectedly, heating the
mono carbodiimido complex 13 at 80 ꢁC does not convert

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Y.-J. Kim et al. / Inorganica Chimica Acta 361 (2008) 2159–2165
˚
Fig. 3. ORTEP drawing of 12. Selected bond lengths (A) and angles (ꢁ): Pd1–C16 2.003(3), Pd1–N1 2.093(3), Pd1–P1 2.3055(9), Pd1–P2 2.3551(9), N1–C7
1.126(5), N2–C7 1.248(5), N2–C8 1.393(5), N3–C16 1.283(4), N3–C17 1.407(4); C16–Pd1–N1 177.23(12), C16–Pd1–P1 91.52(8), N1–Pd1–P1 91.05(11),
C16–Pd1–P2 90.94(8), N1–Pd1–P2 86.64(11), P1–Pd1–P2 172.31(4), C7–N1–Pd1 167.8(4), C7–N2–C8 131.2(4), C16–N3–C17 126.3(3), N1–C7–N2
169.5(5).
CN
L
L
L
N
R
Pd N3
R
Pd
N
C
N
N
N
R
Pd
- N2
N
L
L
L
Ph
N
N
,
R =
N
N
N
N
15
L = PMe3, 13
L = PMe2Ph, 14
Scheme 4.
˚
Fig. 4. ORTEP drawing of 14. Selected bond lengths (A) and angles (ꢁ): Pd1–C17 1.994(3), Pd1–N1 2.038(3), Pd1–P1 2.3171(8), Pd1–P2 2.3241(8), N1–C24
1.174(5), N2–C24 1.241(5), N3–C17 1.324(4), N3–N4 1.356(5), N4–N5 1.285(5), N5–N6 1.368(4), N6–C17 1.349(5); C17–Pd1–N1 177.23(14), C17–Pd1–P1
90.28(9), N1–Pd1–P1 89.88(9), C17–Pd1–P2 91.64(8), N1–Pd1–P2 87.90(9), P1–Pd1–P2 173.38(4), C24–N1–Pd1 150.9(3), C24–N2–C25 124.2(4), C17–
N3–N4 107.1(3), N5–N4–N3 111.1(3), N4–N5–N6 106.0(3), C17–N6–N5 108.7(3).

Y.-J. Kim et al. / Inorganica Chimica Acta 361 (2008) 2159–2165
2163
BX spectrophotometer. NMR (1H, 13C{1H}, and
31P{1H}) spectra were obtained in CDCl3 on a JEOL Lam-
da 300 MHz spectrometer. Chemical shifts were referenced
to internal Me4Si and to external 85% H3PO4. Complexes
trans-[PdEt2L2] (L = PMe3 and PMe2Ph) were prepared
by the literature method [15]. 2,6-Diethylphenyl isocyanide
was prepared as described in the literature [19].
The starting complexes, trans-[PdCl(1-phenyl-1-tetrazol-
yl)(PMe3)2] (1, 83%), [PdCl(1-phenyl-5-tetrazolyl)(PMe2-
Ph)2] (2, 92%), [PdCl(2-thienyl)(PMe3)2] (3, 54% ), [PdCl(2-
pyrazinyl)(PMe3)2] (4, 72%) and [PdCl(2-pyridyl)(PMe3)2]
(5, 74%), were prepared analogously by literature methods
[16b,17].
L
(A)
(B)
L
N
N
N
N
C N
Pd
N
C
C N
Pd
N
N
C
C
N
N
L
L
L
Y
Y
N
L
L
Y
N
N
N
N
Y
C N
M
N
N
Y
M
Y
N
L
Y
Y
(Y = Me, Et)
Scheme 5.
the 1-phenyl-5-tetrazolato ring (Scheme 5A) into the corre-
sponding carbodiimido group. As shown in Schemes 4 and
5, the subsequent formation of the Pd–bis(carbodiimido)
complexes (Scheme 5A) via the nitrogen extrusion from
the tetrazolato rings in 13 and 14 was not observed. In con-
trast, we previously reported that reactions of the bis(a-
zido)–Pd(II) or –Pt(II) complexes with aryl isocyanides
ultimately gave bis(carbodiimido) complexes [M(N@C@
N–Ar)2L2] via the intermediate tetrazolyl M(II) carbodiim-
ide [M{CN4(Ar)}(N@C@N–Ar0)L2] (Scheme 5B). There-
fore, these results indicate that the formation of the
carbodiimido group is dominated by the steric bulk rather
than the electronic factor of the substituents on the hetero-
cyclic ligand.
In summary, we examined the reactivity of the bis(phos-
phine) Pd–azido complexes having heterocyclic ligands
toward organic isocyanides. The isocyanides inserted into
the Pd–C (heterocyclic) or Pd–N (azido) bond to give
Pd–imidoyl or Pd–imidoyl–carbodiimide complexes,
depending on the nature of the heterocyclic ligands.
Whereas the isocyanide insertion into Pd–C bond (hetero-
cycles) does not occur for the bis(phosphine) Pd–azido
complexes containing tetrazolyl or pyrazinyl heterocyclic
ligand, it does occur for the thienyl Pd complex to give
an imidoyl Pd carbodiimide. This reactivity maybe due to
higher electron-withdrawing property or electron delocal-
ization of the tetrazolyl or pyrazinyl group compared with
the thienyl group toward organic isocyanide. Earlier works
by Mantovani and co-workers [8] described that isocyanide
insertion into 2-pyridyl Pd bromide is slower than that into
the thienyl Pd complex, due to the higher electronegativity
of nitrogen compared with sulfur. This work provides a
synthetic route to various Pd–carbodiimido complexes hav-
ing heterocyclic ligands as well as mechanistic aspects for
their formation.
Further treatments of 1–5 with NaN3 have been made
(see Sections 3.1–3.3).
3.1. Reactions of [Pd(R)XL2] (R = 1-phenyl-5-tetrazolyl,
2-thienyl and 2-pyrazinyl ) with NaN3
To a Schlenk flask containing 1 (0.433 g, 0.99 mmol)
were added CH2Cl2 (3 cm3) and
a NaN3 solution
(0.128 g, 1.97 mmol) dissolved in H2O (2 cm3) in that
order. After stirring for 11 h at room temperature, the sol-
vent was completely evaporated to give pale yellow solids,
which were extracted with CH2Cl2. Recrystallization from
CH2Cl2/hexane gave pale yellow solids of [PdN3(1-phenyl-
5-tetrazolyl)(PMe3)2] (6) (0.258 g, 77%). Anal. Calc. for
C13H23N7P2Pd: C, 35.03; H, 5.20; N, 22.00. Found: C,
35.00; H, 5.09; N, 22.48%.
Complexes [PdN3(1-phenyl-5-tetrazolyl)(PMe2Ph)2] (7,
89%), [PdN3(2-thienyl)(PMe3)2] (8, 76%), [PdN3(2-pyrazi-
nyl)(PMe3)2] (9, 58%), and [PdN3(2-pyridyl)(PMe3)2] (10,
77%) were prepared analogously.
Complex 7: Anal. Calc. for C23H27N7P2Pd: C, 48.47; H,
4.78; N, 17.21. Found: C, 48.76; H, 4.83; N, 17.00%. Com-
plex 8: Anal. Calc. for C10H21N3P2SPd: C, 31.30; H, 5.52;
N, 10.95. Found: C, 31.59; H, 5.50; N, 10.83%. Complex
9: Anal. Calc. for C10H21N5P2Pd: C, 31.63; H, 5.57; N,
18.45. Found: C, 31.38; H, 5.59; N, 17.93%. Complex 10:
Anal. Calc. for C11H22N4P2Pd: C, 34.89; H, 5.86; N,
14.80. Found: C, 34.53; H, 5.79; N, 14.21%.
3.2. Reactions of [PdN3 (2-thienyl)(PMe3)2] and
[PdBr(2-thienyl)(PMe3)2] with CN-2,6-Me2C6H3
To a Schlenk flask containing [PdN3(2-thienyl)(PMe3)2]
(0.284 g, 0.74 mmol) were added CH2Cl2(5 ml) and CN–Ar
(Ar = 2,6-Me2C6H3) (0.194 g, 1.48 mmol) in that order.
The initial colorless solution immediately turned to a pale
yellow solution with evolution of nitrogen. After stirring
for 16 h at room temperature, the solvent was completely
evaporated under vacuum, and then the resulting residue
was solidified with diethyl ether. The solids were filtered
off and washed with diethyl ether to give crude solids.
Recrystallization from CH2Cl2/hexane gave pale yellow
crystals of 12, [Pd(N@C@N–Ar){C(@N–Ar)-2-thienyl}-
(PMe3)2 (0.180 g, 39%). Anal. Calc. for C28H39N3P2SPd:
3. Experimental
All manipulations of air-sensitive compounds were per-
formed under N2 or Ar by Schlenk-line techniques. Sol-
vents were distilled from Na–benzophenone. The
analytical laboratories at Basic Science Institute of Korea
and at Kangnung National University carried out elemen-
tal analyses. IR spectra were recorded on a Perkin–Elmer

2164
Y.-J. Kim et al. / Inorganica Chimica Acta 361 (2008) 2159–2165
C, 54.41; H, 6.36; N, 6.80. Found: C, 54.22; H, 6.43; N,
6.64%.
Complex [PdBr{C(@N–Ar0)-2-thienyl}(PMe3)2] (11,
50%) was prepared analogously. Anal. Calc. for
C19H30BrNP2SPd: C, 41.28; H, 5.47; N, 2.53. Found: C,
41.26; H, 5.45; N, 2.42%.
data_request/cif. Supplementary data associated with this
article can be found, in the online version, at
doi:10.1016/j.ica.2007.10.026.
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Organometallics 20 (2001) 2704;
(R = 1-phenyl-5-tetrazoyl) (0.157 g, 0.35 mmol) were
added CH2Cl2 (2 ml) and CN–Ar (Ar = 2,6-Me2C6H3)
(0.047 g, 0.36 mmol) in that order. The initial colorless
solution immediately turned to a pale yellow solution with
N2 evolution. After stirring for 16 h at room temperature,
the solvent was completely evaporated under vacuum, and
then the resulting residue was solidified with diethyl ether.
The solids were filtered off and washed with diethyl ether to
give crude solids. Recrystallization from CH2Cl2/hexane
gave pale yellow crystals of [Pd(R)(N@C@N–Ar)(PMe3)2]
(13, 0.148 g, 77%) (s). Anal. Calc. for C22H32N6P2Pd: C,
48.14; H, 5.88; N, 15.31. Found: C, 48.64; H, 6.25; N,
14.74%.
Complexes [Pd(R)(N@C@N–Ar)(PMe2Ph)2] (R = 1-
phenyl-5-tetrazolyl) (14, 58%) and [Pd(R)(N@C@N–
Ar)(PMe3)2] (R0 = 2-pyrazinyl) (15, 69%) were prepared
analogously.
Complex 14: Anal. Calc. for C32H36N6P2Pd: C, 57.11;
H, 5.39; N, 12.49. Found: C, 57.24; H, 5.45; N, 12.63%.
Complex 15: Anal. Calc. for C19H30N4P2Pd: C, 47.26; H,
6.26; N, 11.60. Found: C, 46.37; H, 6.56; N, 11.10%.
(c) J. Vicente, J.A. Abad, A.D. Frankland, J. Lopez-Serrano, M.C.
Ramirez de Arellano, P.G. Jones, Organometallics 21 (2002) 272;
(d) J. Vicente, I. Saura-Llamas, C. Grunwald, C. Alcaraz, P.G. Jones,
¨
D. Bautista, Organometallics 21 (2002) 3587;
(e) J. Vicente, J.A. Abad, E. Martinez-Viviente, P.G. Jones, Organo-
metallics 21 (2002) 4454;
3.4. X-ray structure determination
(f) J. Vicente, J.A. Abad, E. Martinez-Viviente, P.G. Jones, Organo-
metallics 22 (2003) 1967;
(g) J. Vicente, J.A. Abad, R. Clemente, J. Lopez-Serrano, M.C.
Ramirez de Arellano, P.G. Jones, D. Bautista, Organometallics 22
(2003) 4248;
(h) J. Vicente, J.A. Abad, F.S. Hernandez-Mata, B. Rink, P.G. Jones,
M.C. Ramirez de Arellano, Organometallics 23 (2004) 1292;
(i) J. Vicente, J.A. Abad, M.J. Lopez-Saez, W. Fo¨rtsch, P.G. Jones,
Organometallics 23 (2004) 4414;
(j) J. Vicente, J.A. Abad, J. Lopez-Serrano, P.G. Jones, Organome-
tallics 23 (2004) 4711;
All X-ray data were collected with a Siemens P4 diffrac-
tometer equipped with a Mo X-ray tube. Intensity data
were empirically corrected for absorption with v-scan data.
All calculations were carried out with the use of SHELXTL
programs [20]. All structures were solved by direct meth-
ods. Unless otherwise stated, all non-hydrogen atoms were
refined anisotropically. All hydrogen atoms were generated
in ideal positions and refined in a riding mode.
Details on crystal data, intensity collection, and refine-
ment details are given in Table 1.
(k) J. Vicente, A. Arcas, J.M. Fernandez-Hernandez, D. Bautista,
P.G. Jones, Organometallics 24 (2005) 2516.
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Acknowledgement
This work was supported by the NURI -2006-006 of
Gangwon Advanced Materials.
(b) G.R. Owen, R. Vilar, A.J.P. White, D.J. Williams, Organome-
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Appendix A. Supplementary material
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