Synthesis and characterization of monomeric siloxo palladium(II) complexes: Crystal structure of [Pd(tmeda)(C6F5)(OSiPh3)]

Article abstract of DOI:10.1016/j.jorganchem.2004.03.009

Mononuclear palladium-hydroxo complexes of the type [Pd(N-N)(C₆F₅)(OH)] [(N-N)=2,2′-bipyridine (bipy), 4,4′-dimethyl-2,2′-bipyridine (Me₂bipy), or N,N,N′, N′-tetramethylethylenediamine (tmeda)] react with silanols HOSiR

Full text of DOI:10.1016/j.jorganchem.2004.03.009

Journal of Organometallic Chemistry 689 (2004) 1872–1875
www.elsevier.com/locate/jorganchem
Synthesis and characterization of monomeric siloxo palladium(II)
complexes: crystal structure of [Pd(tmeda)(C6F5)(OSiPh3)]
a,
Jose Ruiz , Consuelo Vicente , Venancio Rodrıguez , Natalia Cutillas ,
a
a
a
*
ꢀ
ꢀ
Gregorio Lopez , Carmen Ramırez de Arellano
a
b
ꢀ
ꢀ
a
Departamento de Quꢀımica Inorgꢀanica, Universidad de Murcia, Campus de Espinardo, 30071 Murcia, Spain
b
Departamento de Quꢀımica Orgꢀanica, Universidad de Valencia, 46100 Valencia, Spain
Received 6 February 2004; accepted 11 March 2004
Abstract
Mononuclear palladium-hydroxo complexes of the type [Pd(N–N)(C6F5)(OH)] [(N–N) ¼ 2,20-bipyridine (bipy), 4,40-dimethyl-
2,20-bipyridine (Me2bipy), or N,N,N0,N0-tetramethylethylenediamine (tmeda)] react with silanols HOSiR3 in toluene giving the
corresponding siloxo complexes [Pd(N–N)(C6F5)(OSiR3)]. The X-ray crystal structure of [Pd(tmeda)(C6F5)(OSiPh3)] has been
determined. In one of the two molecules in the asymmetric unit there is an intramolecular interaction by phenyl–pentafluorophenyl
p-stacking.
ꢀ 2004 Elsevier B.V. All rights reserved.
Keywords: Palladium complexes; Siloxo complexes; Crystal structure
1. Introduction
2. Experimental
Molecular complexes incorporating M–O–Si bonds
(M ¼ transition metal) are good models for metal com-
plexes immobilized on silica and/or silicated surfaces,
which have been commonly used in catalysis [1–3].
While complexes of early transition elements containing
siloxy ligands are well known and characterized, the
data on the late transition metal–siloxide complexes in
molecular form are scarce [3]. The very recently reported
mono-siloxides of Pt(II) and Pd(II) of the type
2.1. Materials and physical measurements
C, H, and N analyses were performed with a Carlo
Erba model EA 1108 microanalyzer. Decomposition
temperatures were determined with a Mettler TG-50
thermobalance at a heating rate of 5 ꢁC minꢀ1 and the
solid samples under nitrogen flow (100 ml minꢀ1). The
1H and 19F NMR spectra were recorded on a Bruker
AC 200E or Varian Unity 300 spectrometer, using
SiMe4 and CFCl3 as the standard, respectively. Infrared
spectra were recorded on a Perkin–Elmer 1430 spec-
trophotometer using Nujol mulls between polyethylene
sheets.
The starting complexes [Pd(N–N)(C6F5)(OH)] [(N–
N) ¼ 2,20-bipyridine (bipy), 4,40-dimethyl-2,20-bipyridine
(Me2bipy), or N,N,N0,N0-tetramethylethylenediamine
(tmeda)] were prepared by procedures described else-
where [5]. The commercially available chemicals were
purchased from Aldrich Chemical Co. and were used
without further purification. Solvents were dried by the
usual methods.
[M(COD)(R)(OSiPh3)]
(COD ¼ 1,5-cycloctadiene;
R ¼ Me, Et, Ph; M ¼ Pt, Pd) have been proved to be
useful precursors of metallic nanoclusters [4]. In this
paper, we report the synthesis and characterization of a
new series of stable siloxo-palladium complexes of the
type [Pd(N–N)(C6F5)(OSiR3)], including the first crystal
structure of a siloxo-palladium complex [3D Search
using the Cambridge Structural Database, July 2003
release].
* Corresponding author. Tel.: +34968367455; fax: +34968364148.
E-mail address: jruiz@um.es (J. Ruiz).
0022-328X/$ - see front matter ꢀ 2004 Elsevier B.V. All rights reserved.
doi:10.1016/j.jorganchem.2004.03.009

J. Ruiz et al. / Journal of Organometallic Chemistry 689 (2004) 1872–1875
1873
2.2. Preparation of [Pd(N–N)(C6F5)(OSiR3)] [N–
N ¼ bipy, R3 ¼ Ph3 (1), Et3 (2) or Me2But (3);
N–N ¼ Me2bipy, R3 ¼ Ph3 (4), Et3 (5) or Me2But (6);
N–N ¼ tmeda, R3 ¼ Ph3 (7), Et3 (8) or Me2But (9)]
3.8%. m.p.: 199 dec. IR (Nujol, cmꢀ1): 792 (Pd–C6F5).
1H NMR ((CD3)2CO): d 8.87 (d, 1H, Ha, J(HaHb) ¼ 5.5
0
0
Hz), 8.38 (s, 2H, Hd + Hd ), 7.77 (d, 1H, Ha ,
0
0
J(Ha Hb ) ¼ 5.8 Hz), 7.5 (m, 6H, Hm of Ph), 7.2 (m, 11H,
0
Hb + Hb + Ho + Hp of Ph), 2.57 (s, 3H, CH3), 2.51
To a solution or suspension of [Pd(N–N)(C6F5)(OH)]
(0.245 mmol) in toluene (12 cm3) was added the corre-
sponding R3SiOH (0.245 mmol) and the resulting solu-
tion was refluxed for 4 h. Then the solvent was partially
evaporated under reduced pressure. On addition of
hexane the yellow complexes precipitated and were fil-
tered off and air-dried.
(s, 3H, CH3). 19F NMR ((CD3)2CO): d )117.1 (d, 2Fo,
Jom ¼ 22:6 Hz), )162.5 (t, 1Fp, Jpm ¼ 19:2 Hz), )164.2
(m, 2Fm).
2.2.5. [Pd(Me2bipy)(C6F5)(OSiEt3)] (5)
Yield: 100 mg, 69%. Anal. Found: C, 48.6; H, 4.5; N,
4.6. Calc. for C24H27F5N2OPdSi: C, 48.9; H, 4.6; N,
4.8%. m.p.: 237 dec. IR (Nujol, cmꢀ1): 790 (Pd–C6F5). 1H
NMR ((CD3)2CO): d 8.88 (d, 1H, Ha, J(HaHb) ¼ 5.5 Hz),
2.2.1. [Pd(bipy)(C6F5)(OSiPh3)] (1)
0
0
0
0
8.37 (s, 2H, Hd + Hd ), 7.85 (d, 1H, Ha , J(Ha Hb ) ¼ 5.8
Yield: 111 mg, 64%. Anal. Found: C, 57.6; H, 3.2; N,
4.1. Calc. for C34H23F5N2OPdSi: C, 57.9; H, 3.3; N,
4.0%. m.p.: 199 dec. IR (Nujol, cmꢀ1): 794 (Pd–C6F5).
0
Hz), 7.69 (d, 1H, Hb, J(HaHb) ¼ 5.5 Hz), 7.32 (d, 1H, Hb ,
0
0
J(Ha Hb ) ¼ 5.8 Hz), 2.60 (s, 3H, CH3 of Me2bipy), 2.51
(s, 3H, CH3 of Me2bipy), 0.87 (t, 9H, CH3 of Et,
J(HH) ¼ 7.9 Hz), 0.19 (q, 6H, CH2 of Et, J(HH) ¼ 7.9
Hz). 19F NMR ((CD3)2CO): d )115.6 (d, 2Fo, Jom ¼ 22:6
Hz), )162.6 (t, 1Fp, Jpm ¼ 19:2 Hz), )164.6 (m, 2Fm).
1H NMR ((CD3)2CO):
d
9.06 (dd, 1H, Ha,
J(HaHb) ¼ 5.4 Hz, J(HaHc) ¼ 1.3 Hz), 8.54 (d, 2H,
0
0
0
Hd + Hd , J(HcHd) ¼ J(Hc Hd ) ¼ 7.6 Hz), 8.28 (m, 2H,
0
0
0
0
Hc + Hc ), 7.97 (d, 1H, Ha , J(Ha Hb ) ¼ 5.6 Hz), 7.74 (m,
0
1H, Hb), 7.5 (m, 7H, Hb + Hm of Ph), 7.2 (m, 9H,
Ho + Hp of Ph). 19F NMR ((CD3)2CO): d )117.3 (d,
2Fo, Jom ¼ 22:6 Hz), )162.3 (t, 1Fp, Jpm ¼ 19:2 Hz),
)164.0 (m, 2Fm).
2.2.6. [Pd(Me2bipy)(C6F5)(OSiMe2But)] (6)
Yield: 114 mg, 79%. Anal. Found: C, 48.6; H, 4.4; N,
4.5. Calc. for C24H27F5N2OPdSi: C, 48.9; H, 4.6; N,
4.8%. m.p.: 239 dec. IR (Nujol, cmꢀ1): 792 (Pd–C6F5).
1H NMR ((CD3)2CO): d 8.91 (d, 1H, Ha, J(HaHb) ¼ 5.5
2.2.2. [Pd(bipy)(C6F5)(OSiEt3)] (2)
0
0
Hz), 8.36 (s, 2H, Hd + Hd ), 7.83 (d, 1H, Ha ,
Yield: 95 mg, 69%. Anal. Found: C, 46.9; H, 4.0; N,
4.8. Calc. for C22H23F5N2OPdSi: C, 47.1; H, 4.1; N,
5.0%. m.p.: 246 dec. IR (Nujol, cmꢀ1): 792 (Pd–C6F5).
1H NMR ((CD3)2CO): d 9.07 (d, 1H, Ha, J(HaHb) ¼ 5.2
0
0
J(Ha Hb ) ¼ 5.8 Hz), 7.69 (d, 1H, Hb, J(HaHb) ¼ 5.5 Hz),
0
0
0
7.31 (d, 1H, Hb , J(Ha Hb ) ¼ 5.8 Hz), 2.60 (s, 3H, CH3
of Me2bipy), 2.51 (s, 3H, CH3 of Me2bipy), 0.85 (s, 9H,
CH3 of But), )0.43 (s, 6H, CH3Si). 19F NMR
((CD3)2CO): d )115.7 (d, 2Fo, Jom ¼ 23:4 Hz), )162.6 (t,
1Fp, Jpm ¼ 19:5 Hz), )164.7 (m, 2Fm).
0
0
0
Hz), 8.54 (d, 2H, Hd + Hd , J(HcHd) ¼ J(Hc Hd ) ¼ 8.0
0
Hz), 8.29 (m, 2H, Hc + Hc ), 8.06 (d, 1H, Ha ,
0
0
0
0
J(Ha Hb ) ¼ 5.2 Hz), 7.88 (m, 1H, Hb), 7.52 (m, 1H, Hb ),
0.84 (t, 9H, CH3 of Et, J(HH) ¼ 7.9 Hz), 0.19 (q, 6H,
CH2 of Et, J(HH) ¼ 7.9 Hz). 19F NMR ((CD3)2CO): d
)115.7 (d, 2Fo, Jom ¼ 21:4 Hz), )162.5 (t, 1Fp,
Jpm ¼ 20:3 Hz), )164.6 (m, 2Fm).
2.2.7. [Pd(tmeda)(C6F5)(OSiPh3)] (7)
Yield: 111 mg, 68%. Anal. Found: C, 54.0; H, 4.5; N,
4.0. Calc. for C30H31F5N2OPdSi: C, 54.2; H, 4.7; N,
4.2%. m.p.: 183 dec. IR (Nujol, cmꢀ1): 790 (Pd–C6F5).
1H NMR ((CD3)2CO): d 7.5 (m, 6H, Hm of Ph), 7.18 (m,
9H, Ho + Hp of Ph), 2.87 (m, 4H, CH2), 2.68 (s, 6H,
CH3), 2.54 (s, 6H, CH3). 19F NMR ((CD3)2CO):
d )117.8 (d, 2Fo, Jom ¼ 22:8 Hz), )163.0 (t, 1Fp,
Jpm ¼ 20:3 Hz), )164.7 (m, 2Fm).
2.2.3. [Pd(bipy)(C6F5)(OSiMe2But)] (3)
Yield: 81 mg, 59%. Anal. Found: C, 46.9; H, 4.0; N,
4.6. Calc. for C22H23F5N2OPdSi: C, 47.1; H, 4.1; N,
5.0%. m.p.: 223 dec. IR (Nujol, cmꢀ1): 788 (Pd–C6F5).
1H NMR ((CD3)2CO):
d
9.02 (dd, 1H, Ha,
J(HaHb) ¼ 5.4 Hz, J(HaHc) ¼ 1.3 Hz), 8.54 (d, 2H,
0
0
0
Hd + Hd , J(HcHd) ¼ J(Hc Hd ) ¼ 8.1 Hz), 8.34 (m, 1H,
2.2.8. [Pd(tmeda)(C6F5)(OSiEt3)] (8)
0
0
0
0
Hc), 8.24 (m, 1H, Hc ), 8.06 (d, 1H, Ha , J(Ha Hb ) ¼ 5.7
Yield: 94 mg, 74%. Anal. Found: C, 41.4; H, 6.0; N,
5.3. Calc. for C18H31F5N2OPdSi: C, 41.5; H, 6.0; N,
5.4%. m.p.: 217 dec. IR (Nujol, cmꢀ1): 786 (Pd–C6F5).
1H NMR ((CD3)2CO): d 2.85 (m, 4H, CH2 of tmeda),
2.66 (s, 6H, CH3 of tmeda), 2.52 (s, 6H, CH3 of tmeda),
0.78 (t, 9H, CH3 of Et, J(HH) ¼ 7.9 Hz), 0.01 (q, 6H,
CH2 of Et, J(HH) ¼ 7.9 Hz). 19F NMR ((CD3)2CO): d
)116.0 (d, 2Fo, Jom ¼ 23:7 Hz), )163.3 (t, 1Fp,
Jpm ¼ 20:3 Hz), )165.2 (m, 2Fm).
0
Hz), 7.84 (m, 1H, Hb), 7.52 (m, 1H, Hb ), 0.83 (s, 9H,
CH3 of But), )0.42 (s, 6H, CH3Si). 19F NMR
((CD3)2CO): d )115.8 (d, 2Fo, Jom ¼ 22:6 Hz), )162.4
(t, 1Fp, Jpm ¼ 20:3 Hz), )164.5 (m, 2Fm).
2.2.4. [Pd(Me2bipy)(C6F5)(OSiPh3)] (4)
Yield: 142 mg, 79%. Anal. Found: C, 58.8; H, 3.5; N,
3.6. Calc. for C36H27F5N2OPdSi: C, 59.0; H, 3.7; N,

1874
J. Ruiz et al. / Journal of Organometallic Chemistry 689 (2004) 1872–1875
2.2.9. [Pd(tmeda)(C6F5)(OSiMe2But)] (9)
C6F5
OH
C6F5
L
L
L
+ HOSiR3
- H2O
Yield: 82 mg, 64%. Anal. Found: C, 41.3; H, 5.7; N,
5.6. Calc. for C18H31F5N2OPdSi: C, 41.5; H, 6.0; N,
5.4%. m.p.: 169 dec. IR (Nujol, cmꢀ1): 788 (Pd–C6F5).
1H NMR ((CD3)2CO): d 2.85 (m, 4H, CH2 of tmeda),
2.67 (s, 6H, CH3 of tmeda), 2.51 (s, 6H, CH3 of tmeda),
0.70 (s, 9H, CH3 of But), )0.58 (s, 6H, CH3Si). 19F
NMR ((CD3)2CO): d )116.2 (d, 2Fo, Jom ¼ 23:4 Hz),
)163.3 (t, 1Fp, Jpm ¼ 19:2 Hz), )165.2 (m, 2Fm).
Pd
Pd
L
OSiR3
L2
R3
1
2
3
4
5
6
7
8
9
bipy
bipy
bipy
Ph3
Et3
Me2But
Me2bipy Ph3
Me2bipy Et3
Me2bipy Me2But
2.3. Crystal structure determination of [Pd(tmeda)-
(C6F5)(OSiPh3)] (7)
tmeda
tmeda
tmeda
Ph3
Et3
Me2But
Yellow prism of 0.72 · 0.10 · 0.10 mm size grown by
n-hexane/toluene diffusion, triclinic, space group P1,
ꢁ
ꢂ
ꢂ
ꢂ
a ¼ 14:9881ð10Þ A, b ¼ 15:6266ð9Þ A, c ¼ 16:4034ð9Þ A,
a ¼ 85:148ð4Þꢁ, b ¼ 63:946ð5Þꢁ, c ¼ 61:553ð4Þꢁ, V ¼
Scheme 1.
3
ꢂ
2996:7ð3Þ A , Z ¼ 4, 2hmax ¼ 50ꢁ, diffractometre Sie-
ꢂ
mens P4, Mo Ka (k ¼ 0:71073 A), x-scan, T ¼ 173ð2Þ
H
H
δ
H
δ
H
H
H
Me
δ
Me
H
δ'
γ'
γ
'
K, 15 402 reflections collected of which 8399 were in-
dependent, Rint ¼ 0:0124, direct primary solution and
refinement on F 2 using SHELX-97 program [6], 771 re-
fined parameters, the tmeda groups of both independent
molecules are disordered over two sites [occupancy
82.8(7)/17.2(7)% and 76.9(9)/23.1(9)%], hydrogen atoms
were refined using a riding model, R1 [I > 2rðIÞ] ¼
H
H
β'
β'
H
H
β
β
N
N
N
N
H
H
α
H
α
α'
α'
Pd
Pd
C F
C F
6 5
X
X
6
5
Me
Me
Me
Me
N
N
Pd
0.0265, wR2 (all data) ¼ 0.0707, max D=r ¼ 0:001, max
C F
X
6
5
ꢂꢀ3
Dq ¼ 0:22 e A
.
Scheme 2.
3. Results and discussion
given in Scheme 2. The low-field resonance (d 8.8–9.1) in
complexes 1–6 is assigned to the a-H atom [15]. Reso-
nances of the methyl protons of the siloxy group in
complexes 3, 6 and 9 appears as a singlet at )0.42, )0.43
and )0.58, respectively [16]. The 19F NMR spectra show
the expected three resonances for 2Fo:1Fp:2Fm of the
C6F5 ligand.
The reactions of the triphenylsiloxo complex 7 with
the unsaturated reagents CO, PhNCO and PhNCS were
tried. When 7 was treated with CO, PhNCO and PhNCS
at room temperature in toluene, the unchanged complex
7 was recovered, and the reaction of CO with 7 under
refluxing toluene led to the formation of metallic
palladium.
The reaction of the monomeric hydroxo palladium
complex [Pd(N–N)(C6F5)(OH)] (N–N ¼ bipy, Me2bipy,
or tmeda) with silanol HOSiR3 in toluene gives the
corresponding siloxo complex [Pd(N–N)(C6F5)(OSiR3)]
1–9 (Scheme 1) in 59–79% yield. The acidic proton of the
silanol is abstracted by the corresponding hydroxo-
complex generating the anionic ligand R3SiOꢀ with is
subsequently trapped by the organometallic moiety
[Pd(N–N)(C6F5)]þ to form complexes 1–9 and the
concomitant release of water. The structures were as-
1
signed on the basis of microanalytical, IR, and H and
19F NMR data. Complexes 1–9 are all air-stable solids
and the thermal analysis shows that they decompose
above 169 ꢁC in a dynamic N2 atmosphere. The IR
spectra show the characteristic absorptions of the C6F5
group [7] at 1630, 1490, 1450, 1050, 950 and a single
band at ca. 800 cmꢀ1 which is derived from the so-called
X-sensitive mode [8] in C6F5 halogen molecules, which is
characteristic of the presence of only one C6F5 group in
the coordination sphere of the palladium atom and be-
haves like a m(M–C) band [9–11]. The characteristic
resonances of the neutral ligands [5,12–15] were ob-
served in the 1H NMR spectra and the assignments
presented in Section 2 are based on the atom numbering
3.1. X-ray structure of [Pd(tmeda)(C6F5)(OSiPh3)]
(7)
Fig. 1 shows the X-ray structure of complex 7, with
selected bond lengths and angles listed in Table 1. The
crystal structure of compound 7 shows two independent
molecules in the asymmetric unit with the palladium
atom in a slightly distorted square planar geometry.
ꢂ
The Pd–O bond length (1.986(3) A) is in the typical
range of Pd–O bonds reported for phenoxo palladium
complexes [17,18] and slightly shorter than that found in

J. Ruiz et al. / Journal of Organometallic Chemistry 689 (2004) 1872–1875
1875
4. Supplementary material
Crystallographic data for the structural analysis of
compound 7 have been deposited with the Cambridge
Crystallographic Data Centre, CCDC No. 230611.
Copies of this information may be obtained free of
charge from The Director, CCDC, 12 Union Road,
Cambridge, CB2 1EZ, UK (fax: +44-1223-336033;
e-mail: deposit@ccdc.cam.ac.uk or www: http://www.
ccdc.cam.ac.uk).
Acknowledgements
Fig. 1. Ellipsoid plot (30% probability) of compound [Pd(tmeda)-
(C6F5)(OSiPh3)] with the molecular labelling.
ꢀ
This work was supported by the Direccion General
ꢀ
ꢀ
de Investigacion del Ministerio de Ciencia y Tecnologıa
(Project No. BQU2001-0979-C02-01), Spain, and the
Table 1
ꢂ
ꢀ
Fundacion Seneca de la Comunidad Autonoma de la
Region de Murcia (Project No. PI-72-00773-FS-01).
ꢀ
ꢀ
Selected bond lengths (A) and angles (ꢁ) for complex 7
ꢀ
Bond lengths
Bond angles
Molecule 1
Pd(1)–O(1)
Pd(1)–C(11)
Pd(1)–N(1)
Pd(1)–N(2)
Si(1)–O(1)
1.986(3)
1.997(4)
2.055(4)
2.128(4)
1.589(3)
C(11)–Pd(1)–N(1)
C(11)–Pd(1)–N(2)
N(1)–Pd(1)–N(2)
O(1)–Pd(1)–N(2)
O(1)–Pd(1)–N(1)
O(1)–Pd(1)–C(11)
Pd(1)–O(1)–Si(1)
93.2(2)
176.4(2)
84.5(2)
References
88.89(14)
173.3(2)
93.3(2)
[1] F.R. Hartley, Supported Metal Complexes, Reidel, Boston, 1985.
[2] Y. Iwasawa (Ed.), Tailored Metal Catalysis, Reidel, Boston, 1986.
[3] B. Marciniec, H. Maciejewski, Coord. Chem. Rev. 223 (2001) 301.
[4] A. Fukuoka, A. Soto, K. Kodama, M. Hirano, S. Komiya, Inorg.
Chim. Acta 294 (1999) 266.
137.9(2)
Molecule 2
Pd(1A)–O(1A) 1.984(3)
Pd(1A)–C(11A) 1.993(5)
Pd(1A)–N(1A) 2.068(5)
Pd(1A)–N(2A) 2.135(5)
C(11A)–Pd(1A)–N(1A) 94.1(2)
C(11A)–Pd(1A)–N(2A) 172.9(2)
ꢀ
[5] J. Ruiz, M.T. Martınez, F. Florenciano, V. Rodrıguez, G. Lopez,
J. Perez, P.A. Chaloner, P.B. Hitchcock, Inorg. Chem. 42 (2003)
ꢀ
ꢀ
ꢀ
N(1A)–Pd(1A)–N(2A)
O(1A)–Pd(1A)–N(2A)
O(1A)–Pd(1A)–N(1A)
O(1A)–Pd(1A)–C(11A)
Pd(1A)–O(1)–Si(1A)
84.9(2)
89.6(2)
3650.
[6] G.M. Sheldrick, SHELX-97, University of Gottingen, Gottingen,
Germany, 1997.
€
€
Si(1A)–O(1A)
1.586(4)
174.5(2)
91.3(2)
136.9(2)
[7] D.A. Long, D. Steel, Spectrochim. Acta 19 (1963) 1955.
[8] E. Maslowski, Vibrational Spectra of Organometallic Com-
pounds, Wiley, New York, 1977, p. 437.
ꢀ
~
[9] E. Alonso, J. Fornies, C. Fortuno, M. Tomas, J. Chem. Soc.,
ꢀ
[Pt(C6F5)2(OC6H4NO2-p)(CO)]ꢀ (Pt–O ¼ 2.070(4) A)
[19]. The Pd–O–Si angle of 137.9(2)ꢁ is in the range of
those for siloxo complexes such as [Pt(COD)(R)(OS-
iPh3)] (R ¼ Ph, Et) [4]. The different Pd–N (Pd(1)–N(2),
ꢂ
Dalton Trans. (1995) 3777.
ꢀ
ꢀ
ꢀ
[10] G. Lopez, J. Ruiz, C. Vicente, J.M. Martı, G. Garcıa, P.A.
Chaloner, P.B. Hitchcock, Organometallics 11 (1992) 4091.
ꢀ
ꢀ
ꢀ
[11] J. Ruiz, M.T. Martınez, C. Vicente, G. Garcıa, G. Lopez, P.A.
Chaloner, P.B. Hitchcock, Organometallics 12 (1993) 4321.
[12] P.K. Byers, A.J. Canty, Organometallics 9 (1990) 210.
[13] Y. Fuchita, Y. Harada, Inorg. Chim. Acta 208 (1993) 43.
[14] G.D. Smith, B.E. Hanson, J.S. Merola, F.J. Waller, Organomet-
allics 12 (1993) 568.
ꢂ
ꢂ
2.128(4) A; Pd(1)–N(1), 2.055(5) A) distances are in
agreement with the higher trans influence of the group
C6F5 compared to OSiPh3. The chelate angle N(1)–
Pd(1)–N(2) (84.5(2)ꢁ) is similar to that found (83.9(2)ꢁ)
in [Pd(tmeda)(C6F5)(CO2Me)] [5]. The Pd–C6F5 bond
ꢀ
ꢀ
[15] J. Fornies, F. Martınez, R. Navarro, E.P. Urriolabeitia, J.
Organomet. Chem. 495 (1995) 185.
ꢂ
length (1.997(4) A) is in the range found in the literature
[16] N. Mintcheva, Y. Nishihara, A. Mori, K. Osakada, J. Organomet.
Chem 629 (2001) 61.
for pentafluorophenyl–palladium complexes [15]. In one
of the molecules in the asymmetric unit there is an in-
tramolecular interaction by phenyl–pentafluorophenyl
p-stacking [20,21]. The planes of both rings make an
angle of 6.2ꢁ, with an interplanar distance (average of
the two distances between the mean plane of one ring
[17] G.M. Kapteijn, M.D. Meijer, D.M. Grove, N. Veldman, A.L.
Spek, G. van Koten, Inorg. Chim. Acta 264 (1997) 211.
[18] X. Liu, S.L. Renard, C.A. Kilner, M.A. Halcrow, Inorg. Chem.
Commun. 6 (2003) 598.
ꢀ
ꢀ
[19] J. Ruiz, V. Rodrıguez, G. Lopez, P.A. Chaloner, P.B. Hitchcock,
Organometallics 15 (1996) 1662.
[20] J.C. Collings, K.P. Roscoe, R.L. Thomas, A.S. Batsanov, L.M.
Stimson, J.A.K. Howard, T.B. Marder, New J. Chem. 25 (2001)
1410.
ꢂ
and the centroide of the other) of 3.51 A, a centre-to-
ꢂ
centre of 3.527 A and a deviation of the centre–centre
line of the perpendicular of the plane of 7.5ꢁ (pentaflu-
orophenyl ring) and 11ꢁ (phenyl ring).
[21] V.R. Vangala, A. Nangia, V.M. Lynch, Chem. Commun. (2002)
1304.