Linear homobimetallic palladium complexes

Article abstract of DOI:10.1016/j.jorganchem.2006.05.034

The oxidative addition of C₆H₄-1,4-I₂ (1) to Pd(PPh₃)₄ (2) gives mononuclear trans-(Ph₃P)₂Pd(C₆H₄-4-I)(I) (3), which can be converted to trans-(Ph₃P)₂Pd(C₆H₄-4-I)(OT f) (5) by its reaction with [AgOTf] (4). Complex 5 can be used in the high-yield preparation of a series of unique cationic mono- and dinuclear palladium complexes of structural type [trans-(Ph₃P)₂Pd(C₆H₄-4-I)(L )]⁺ (7, L = C₄H₄N₂; 9a, L = C₅H₄N-4-C{triple bond, long}N; 9b, L = N{triple bond, long}C-4-C₅H₄N) and [trans-(C₆H₄-4-I)(Ph₃P)₂Pd ← N^∩N → Pd(PPh₃)₂(C₆H₄-4-I)] ²⁺ (14a, N^∩N = C₆H₄-1,4-(C{triple bond, long}N)₂; 14b, N^∩N = (C₆H₄-4-C{triple bond, long}N)₂; 14c, N^∩N = 4,4′-bipyridine (=bipy)). Complexes 7, 9 and 14 rearrange in solution to give [trans-(Ph₃P)₂Pd(C₆H₄-4-PPh ₃)(L)]²⁺ (10, L = C₄H₄N₂; 12a, L = C₅H₄N-4-C{triple bond, long}N; 12b, L = N{triple bond, long}C-4-C₅H₄N) and [trans-(C₆H₄-4-PPh₃)(Ph₃P) ₂Pd ← N^∩N → Pd(PPh₃)₂(C₆H₄-4-PPh ₃)]⁴⁺ (15a, N^∩N = C₆H₄-1,4-(C{triple bond, long}N)₂; 15b, N^∩N = (C₆H₄-4-C{triple bond, long}N)₂) along with {[(Ph₃P)₂(Ph₃P-4-C₆H ₄)Pd(μ-I)]₂}²⁺ (11). The solid state structures of 3, 9a, 10, 11 and 15b are reported. Most characteristic for all complexes is the square-planar coordination geometry of palladium with trans-positioned PPh₃ ligands. In 3 the iodide and the 4-iodo-benzene are linear oriented laying with the palladium atom on a crystallographic C₂ axes. In 9a this symmetry is broken by steric interactions of the PPh₃ ligands with the 4-cyanopyridine and 4-iodobenzene groups. Compound 11 contains two μ-bridging iodides with different Pd-I separations showing that the C₆ H₄ PPh₃⁺ ligand induces a stronger trans-influence than PPh₃. In 15b, the Ph₃PC₆H₄{single bond}Pd ← N{triple bond, long}C{single bond}C₆H₄{single bond}C₆H₄{single bond}C{triple bond, long}N → Pd{single bond}C₆H₄PPh₃ building block is rigid-rod structured with the C₆H₄ units perpendicular oriented to the Pd coordination plane, while the biphenylene connecting moiety is in-plane bound.

Full text of DOI:10.1016/j.jorganchem.2006.05.034

Journal of Organometallic Chemistry 691 (2006) 3834–3845
www.elsevier.com/locate/jorganchem
Linear homobimetallic palladium complexes
a,
a
a
b
Heinrich Lang *, Deeb Taher , Bernhard Walfort , Hans Pritzkow
a
Technische Universita¨t Chemnitz, Fakulta¨t fu¨r Naturwissenschaften, Institut fu¨r Chemie, Lehrstuhl Anorganische Chemie,
Straße der Nationen 62, 09111 Chemnitz, Germany
Anorganisch-chemisches Institut, Ruprecht-Karls-Universita¨t Heidelberg, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany
b
Received 7 April 2006; received in revised form 10 May 2006; accepted 16 May 2006
Available online 3 June 2006
Abstract
The oxidative addition of C6H4-1,4-I2 (1) to Pd(PPh3)4 (2) gives mononuclear trans-(Ph3P)2Pd(C6H4-4-I)(I) (3), which can be con-
verted to trans-(Ph3P)2Pd(C6H4-4-I)(OTf) (5) by its reaction with [AgOTf] (4). Complex 5 can be used in the high-yield preparation
of a series of unique cationic mono- and dinuclear palladium complexes of structural type [trans-(Ph3P)2Pd(C6H4-4-I)(L)]+ (7,
L = C4H4N2; 9a, L = C5H4N-4-C„N; 9b, L = N„C-4-C5H4N) and [trans-(C6H4-4-I)(Ph3P)2Pd N\N ! Pd(PPh3)2(C6H4-4-I)]2+
(14a, N\N = C6H4-1,4-(C„N)2; 14b, N\N = (C6H4-4-C„N)2; 14c, N\N = 4,40-bipyridine (=bipy)). Complexes 7, 9 and 14 rearrange
in solution to give [trans-(Ph3P)2Pd(C6H4-4-PPh3)(L)]2+ (10, L = C4H4N2; 12a, L = C5H4N-4-C„N; 12b, L = N„C-4-C5H4N) and
[trans-(C6H4-4-PPh3)(Ph3P)2Pd N\N ! Pd(PPh3)2(C6H4-4-PPh3)]4+ (15a, N\N = C6H4-1,4-(C„N)2; 15b, N\N = (C6H4-4-C„N)2)
along with {[(Ph3P)2(Ph3P-4-C6H4)Pd(l-I)]2}2+ (11).
The solid state structures of 3, 9a, 10, 11 and 15b are reported. Most characteristic for all complexes is the square-planar coordination
geometry of palladium with trans-positioned PPh3 ligands. In 3 the iodide and the 4-iodo-benzene are linear oriented laying with the
palladium atom on a crystallographic C2 axes. In 9a this symmetry is broken by steric interactions of the PPh3 ligands with the 4-cyano-
pyridine and 4-iodobenzene groups. Compound 11 contains two l-bridging iodides with different Pd–I separations showing that the
C6H4PPhþ ligand induces a stronger trans-influence than PPh3. In 15b, the Ph3PC6H4APd N„CAC6H4AC6H4AC„N !
3
PdAC6H4PPh3 building block is rigid-rod structured with the C6H4 units perpendicular oriented to the Pd coordination plane, while
the biphenylene connecting moiety is in-plane bound.
ꢀ 2006 Elsevier B.V. All rights reserved.
Keywords: Palladium; Homobimetallic; Lewis-bases; 1-Dimensional complexes; X-ray structure
1. Introduction
organometallic building blocks assembled with all-carbon
chains [5], or hetero atom consisting units [6], offer a fasci-
nating perspective for the design of nanoscopic molecular
devices. However, it appeared that, when the chain length
of the bridging unit is increased, the synthesis of the com-
pounds becomes more difficult and the stability of the com-
pounds decreases [6]. Out of this reason, we decided to
systematically study homobimetallic late-transition metal
complexes in which the organometallic fragments are
bridged by p-conjugated nitrogen-containing Lewis-bases
of different length [6,7]. This would enable us to prepare
in a straightforward manner linear transition metal
complexes.
There is a wide interest in the synthesis of one-dimen-
sional molecules [1], because they possess considerable
attention in, for example, the developing field of molecular
electronics [2]. The ability of molecular wires is to transport
in a very efficient way electrons through the wire between
two redox-active fragments [3]. The properties of such
complexes depend on the nature of the redox termini and
the p-conjugated linking units [4]. The use of redox-active
*
Corresponding author. Tel.: +49 371 531 1673; fax: +49 371 531 1833.
E-mail address: heinrich.lang@chemie.tu-chemnitz.de (H. Lang).
0022-328X/$ - see front matter ꢀ 2006 Elsevier B.V. All rights reserved.
doi:10.1016/j.jorganchem.2006.05.034

H. Lang et al. / Journal of Organometallic Chemistry 691 (2006) 3834–3845
3835
We here report full details for the synthesis, the spectral
characterization and X-ray molecular structures of unique
mono- and dinuclear palladium species featuring bidentate
Lewis-base ligands spanning the appropriate organometal-
lic building blocks.
2. Results and discussion
Mononuclear [trans-(Ph3P)2Pd(C6H4-4-I)(L)]+ (7, L =
C4H4N2; 9a, L = C5H4N-4-C„N; 9b, L = N„C-4-C5H4N)
and [trans-(Ph3P)2Pd(C6H4-4-PPh3)(L)]2+ (10, L = C4H4N2;
12a, L = C5H4N-4-C„N; 12b, L = N„C-4-C5H4N) as
well as homobimetallic {[(Ph3P)2(Ph3P-4-C6H4)Pd(l-I)]2}2+
(11),
[trans-(C6H4-4-I)(Ph3P)2Pd N\N ! Pd(PPh3)2-
(C6H4-4-I)]2+ (14a, N\N = C6H4-1,4-(C„N)2; 14b, N\N =
(C6H4-4-C„N)2; 14c, N\N = 4,40-bipyridine (=bipy))
and [trans-(C6H4-4-PPh3)(Ph3P)2Pd N\N ! Pd(PPh3)2-
(C6H4-4-PPh3)]4+ (15a, N\N = C6H4-1,4-(C„N)2; 15b,
N\N = (C6H4-4-C„N)2) can be synthesized from trans-
(Ph3P)2Pd(C6H4-4-I)(OTf) (5) (OTf = triflate, OSO2CF3).
Complex 5 itself is accessible in a two-step synthesis proce-
dure as shown in Eq. (1). An irreversible chemoselective
oxidative addition of C6H4-1,4-I2 (1) to Pd(PPh3)4 (2) gives
the insertion product trans-(Ph3P)2Pd(C6H4-4-I)(I) (3) [8].
The palladium-bonded iodide in 3 can be exchanged for
more label triflate to form 5 by the reaction with equimolar
amounts of [AgOTf] (4) in toluene–dichloromethane mix-
tures. Complex 3 could be isolated as a colorless crystalline
material, while compound 5 could only be prepared in situ,
since it is unstable both in solution and in the solid state
and decomposes even at low temperature to give a black
insoluble precipitate [9].
Fig. 1. ORTEP plot (50% probability level) of 3 with the atom numbering
scheme. Hydrogen atoms are omitted for clarity. Selected bond distances
˚
(A) and angles (ꢁ): Pd(1)–P(1) 2.342(2), Pd(1)–P(1A) 2.342(2), Pd(1)–C(19)
2.04(1), Pd(1)–I(2) 2.699(1); and I(2)–Pd(1)–C(19) 180.0, P(1A)–Pd(1)–
P(1) 176.6(1), P(1)–Pd(1)–I(2) 91.70(5), P(1)–Pd(1)–C(19) 88.30(5).
Single crystals of 3, suitable for X-ray diffraction studies
could be grown by slow vapor diffusion of n-pentane into a
dichloromethane solution of 3 at room temperature. The
structure of 3 (Fig. 1) shows a perfect square-planar coor-
dination geometry around Pd1 with trans-oriented PPh3
groups. Complex 3 features a C2 symmetry (symmetry gen-
erated atoms are indicated with the suffix A; symmetry
code 0.5 ꢀ x, y, ꢀz) with the axis lying onto I1, C22,
C19, Pd1 and I2. Thus, the benzene ring is exactly perpen-
dicular oriented to the square plane of the palladium coor-
˚
dinated atoms. The Pd1–P1 separation with 2.342(2) A is
I
Pd(PPh )
3 4
I
+
in the range expected for trans-positioned triphenyl
˚
phosphine ligands (2.319–2.342 A). Both the Pd1–I2
2
1
˚
˚
(2.699(1) A) and the Pd1–C19 distances (2.04(1) A)
(Fig. 1) agree well with those separations reported for other
trans-configurated iodo-palladium-carbon units in which
likewise the Pd–I bond is trans to a C-sp2 donor atom of
high trans-influence [11–16].
PPh
PPh
3
3
[AgOTf] (4)
I
Pd
PPh
I
I
OTf
Pd
- AgI
- 2PPh3
PPh
3
3
Complex 5 can successfully be used in the synthesis
of mononuclear [trans-(Ph3P)2Pd(C6H4-4-I)(L)]+ (7, L =
C4H4N2; 9a, L = C5H4N-4-C„N; 9b, L = N„C-4-C5H4N).
The reaction of 5 with one equivalent of the nitrogen
donors C4H4N2 (6) and C5H4N-4-C„N (8) proceeds essen-
tially quantitatively as outlined in Scheme 1. In an attempt
to synthesize linear molecules of type [trans-(C6H4-
4-I)(Ph3P)2Pd N\N ! Pd(PPh3)2(C6H4-4-I)]2+ (N\N =
C4H4N2, C5H4N-4-C„N) by reacting 5 with 0.5 equiv. of
6 and 8, respectively, also resulted in the formation of
mononuclear 7 and 9. This can be explained by either steric
requirements (solid state structure of 9a) or electronic
effects, since upon coordination of palladium to nitrogen
the second nitrogen atom becomes too electron poor to
interact with a further palladium atom.
3
5
ð1Þ
1
Complex 3 was characterized by elemental analysis, H,
13C{1H} and 31P{1H} NMR and IR spectroscopy (Section
3).
The 31P{1H} NMR spectrum of 3 displays a resonance
signal at 21 ppm. The key spectroscopic H NMR feature
1
of 3 is that the protons of the C6H4-4-I ligand show a dou-
blet-of-doublet (oH) and doublet (mH), attributable to the
ortho and meta hydrogen nuclei, magnetically coupled to
each other over three bonds (oH, mH) and additionally
coupled to the phosphorus nuclei over four bonds (oH)
[10].

3836
H. Lang et al. / Journal of Organometallic Chemistry 691 (2006) 3834–3845
+
-
PPh
OTf
3
I
Pd
N
N
PPh
3
(6)
N
N
7
PPh
3
I
Pd OTf
PPh
3
N
C
N (8)
+
+
5
-
-
OTf
OTf
PPh
Pd
PPh
Pd
3
3
I
N
C N
+
I
N C
N
PPh
PPh
3
3
9b
9a
Scheme 1. Synthesis of mononuclear 7, 9a and 9b.
The most noteworthy feature of complex 9 is that it
exists as two isomers (9a and 9b) differing in the coordi-
nation of the ambident Lewis-base 4-cyanopyridine 8 to
palladium (cyano group or pyridine nitrogen atom
(Scheme 1)). In an independent study we were able to
show that complex 9a, which preferentially crystallizes
in form of colorless single crystals (Fig. 2), rearranges in
solution during days to give a mixture of 9a and 9b,
respectively. The C„N stretching vibration for 9a is
found at 2244 cmꢀ1, while for 9b, where the cyano unit
is datively bonded to palladium, shows one absorption
Pd1–N1 are 173.08(6) and 179.7(2)ꢁ). The aromatic rings
of the C6H4-4-I and C5H4N-4-C„N moieties are, in com-
parison with 3, not perpendicular oriented to the palla-
dium coordination plane (78.9ꢁ for C6H4-4-I and 68.4ꢁ
for C5H4N-4-C„N). This might be effected by sterical
interactions of the benzene rings with the two PPh3
ligands. The Pd1–C1, Pd1–N1, Pd1–P1 and Pd1–P2 bond
distances are in the typical range as reported for similar
palladium complexes [12].
Complexes 7 and 9 are not stable in solution at room
temperature for a long period of time. We observed that
the color of, for example, dichloromethane solutions con-
taining either 7 or 9, changed during days from pale yellow
to orange, whereby elemental palladium precipitated (Eqs.
(2) and (3)). After filtration through a pad of Celite and
addition of n-hexane to the filtrates colorless crystals
of [trans-(C6H4-4-PPh3)(Ph3P)2PdL]2+ (10, L = C4H4N2;
12a, L = C5H4N-4-C„N; 12b, L = N„C-4-C5H4N) are
produced. Concentration of the supernatant solution gave
crystals of {[(Ph3P-4-C6H4)(Ph3P)2Pd(l-I)]2}2+ (11).
at 2277 cmꢀ1
.
Unequivocal conformation of the proposed structure of
9a was obtained from a single-crystal structure determina-
tion. The molecular structure of 9a and relevant bond
lengths and angles are shown in the legend of Fig. 2.
The overall structural features of 9a are similar to those
of related palladium complexes [11,13]. The metal
square-plane is slightly distorted and includes trans-posi-
tioned triphenyl phosphino groups (P1–Pd1–P2 and C1–
2+
-
2O Tf
PPh3
+
OTf -
2+
2OTf -
I
PPh3
Pd
PPh3
Pd
25oC
Ph3P
ð2Þ
I
N
N
Ph3P
N
N
Pd
Pd
+
CH2Cl2 / n-hexane
PPh3
PPh3
PPh3
I
Ph3P
7
11
10
+ Pd +...

H. Lang et al. / Journal of Organometallic Chemistry 691 (2006) 3834–3845
3837
2+
2 OTf -
PPh3
+
+
OTf -
OTf -
I
PPh3
Pd
PPh3
Pd
Ph3P
25 o
C
Pd
Pd
I
N
C N
I
N
C
N
CH2Cl2 / n-hexane
PPh3
I
PPh3
PPh3
Ph3P
9a
9b
11
ð3Þ
2+
2 OTf -
2+
2 OTf -
PPh3
PPh3
Pd
Ph3P
Pd
N
C N
Ph3P
N
N
C
+
PPh3
PPh3
12a
12b
Due to the ionic character of 10–12 they only dissolve in
chlorinated solvents. They are air-, moisture- and tempera-
ture sensitive.
the starting materials 7 and 9, respectively (Section 3). Fur-
ther characteristic is the increase of intensity for the PPh3
protons in 10 and 12 which indicates the presence of a third
PPh3 group and is in agreement with the proposed
structures.
The formation of 10–12 from 7 and 9 most likely sug-
gests a interchange reaction occurring through a P–C
reductive elimination to form the 4-iodo tetraphenyl phos-
phonium cation followed by irreversible palladium medi-
ated oxidative addition of the C–I bond to palladium(0)
as described in Ref. [18].
Most representative for 10 and 12 are their 31P{1H}
NMR spectra, since two resonance signals can be detected
at ca. 21 and 27 ppm [17]. This differs from the starting
materials 7 and 9, where only one resonance signal is found
(7, 9: 21.2 ppm).
Noteworthy for 10 and 12 is the lowfield shift for the oH
and mH protons of the C6H4, 4-cyano pyridine and pyra-
1
zine units in the H NMR spectra, when compared with
Crystals of 10 were grown from diffusion of benzene into
dichloromethane solutions containing 7. The solid-state
structure and selected bond distances and angles of 10
are given in Fig. 3.
The palladium atom Pd1 is held in a distorted square-
planar environment (mean deviation of the atoms Pd1,
˚
P2, P3, N1 and C5 from the best plane is 0.1411 A) with
the coordinated pyrazine unit in a position trans to Cipso
(C5) of the C6H4PPhþ moiety (Fig. 3). This coordination
3
geometry is typical for molecules containing a (Ph3P)2Pd
entity [14,16]. A comparison with compound 9a shows that
the angles between the palladium coordinated aromatic
rings and the palladium coordination plane are in the same
range (84.7ꢁ C6H4 and 68.6ꢁ C4H4N2). The Pd1–C5
˚
˚
˚
(1.997(4) A), Pd1–N1 (2.124(3) A), Pd1–P2 (2.325(1) A)
˚
and Pd1–P3 (2.345(1) A) distances are within the range of
reported palladium-aryl, coordinated-nitrogen heterocycles
and -phosphane bonds [15]. As well, the P1–C8 bond
˚
Fig. 2. ORTEP plot (50% probability level) of 9a with the atom
length resembles with 1.782(4) A to distances characteristic
numbering scheme (the hydrogen atoms, the chloroform molecule and
for this type of structural bonding motif [16,18].
the OTfꢀ ion are omitted for clarity). Selected bond distances (A) and
˚
Colorless crystals of 11 which are suitable for single X-
ray structure determination could be obtained by slow
evaporation of chloroform from dissolved 10 at room tem-
perature (vide supra). The result of the X-ray structure
angles (ꢁ): Pd(1)–P(1) 2.358(2), Pd(1)–P(2) 2.355(2), Pd(1)–C(1) 2.023(6),
Pd(1)–N(1) 2.138(5); and N(1)–Pd(1)–C(1) 179.7(2), P(1)–Pd(1)–P(2)
173.08(6), P(1)–Pd(1)–N(1) 93.0(2), P(1)–Pd(1)–C(1) 87.0(2), N(1)–
Pd(1)–C(1)–C(2)–4(44), C(1)–Pd(1)–N(1)–C(11) 17(44).

3838
H. Lang et al. / Journal of Organometallic Chemistry 691 (2006) 3834–3845
Fig. 3. ORTEP plot (50% probability level) of the asymmetric unit of 10 with the atom numbering scheme (the hydrogen atoms, 1.5 benzene molecules
and the two OTfꢀ ions are omitted for clarity). Selected bond distances (A) and angles (ꢁ): Pd(1)–P(2) 2.325(1), Pd(1)–P(3) 2.345(1), Pd(1)–C(5) 1.997(4),
˚
Pd(1)–N(1) 2.124(3), P(1)–C(8) 1.782(4); and N(1)–Pd(1)–C(5) 173.5(2), P(2)–Pd(1)–P(3) 167.29(4), P(2)–Pd(1)–N(1) 95.24(9), P(2)–Pd(1)–C(5) 86.2(2),
N(1)–Pd(1)–C(5)–C(6) –166.0, C(5)–Pd(1)–N(1)–C(1) –167.7.
Fig. 4. ORTEP plot (50% probability level) of 11 with the atom numbering scheme (the hydrogen atoms, four chloroform molecules and the two OTfꢀ
˚
ions are omitted for clarity). Selected bond distances (A) and angles (ꢁ): Pd(1)–I(1) 2.6566(3), Pd(1)–I(1A) 2.7088(3), Pd(1)–C(19) 2.005(3), Pd(1)–P(1)
2.2748(7), P(2)–C(22) 1.796(3); and I(1)–Pd(1)–I(1A) 86.367(8), I(1)–Pd(1)–P(1) 176.15(2), I(1A)–Pd(1)–P(1) 97.48(2), I(1)–Pd(1)–C(19) 87.56(8), I(1A)–
Pd(1)–C(19) 173.22(8), C(19)–Pd(1)–P(1) 88.60(8), Pd(1)–I(1)–Pd(1A) 93.633(8).
analysis is depicted in Fig. 4; selected bond lengths and
angles are presented in the legend to Fig. 4.
than PPh3. A similar trend has been observed previously
for, e.g. [trans-(PPh3)(Ph)Pd(l-I)]2 and [trans-(PPh3)(PhCO)-
Pd(l-I)]2 [17–19]. All other bond lengths and angles of 11 are
similar to those values found elsewhere [18–20].
The molecule sits on a crystallographic center of symme-
try with the asymmetric unit containing one-half of the
dimer in anti-configuration (Fig. 4). As expected, [trans-
(C6H4-4-PPh3)(PPh3)Pd(l-I]2(OTf)2 (11) displays almost a
ideal square-planar geometry around Pd1. The Pd–I bonds
are different, the one trans to the carbon C19 (Pd1–I1A
The 31P{1H} NMR spectrum of 11 shows two resonance
signals at 21 and 27 ppm (vide supra) [17,18].
The palladium triflate complex 5 can also be applied in
the synthesis of homobimetallic rigid-rod structured [trans-
(C6H4-4-I)(Ph3P)2Pd N\N! Pd(PPh3)2(C6H4-4-I)]2+ (14a,
N\N = C6H4-1,4-(C„N)2; 14b, N\N = (C6H4-4-C„N)2;
14c, N\N = 4,40-bipyridine (=bipy) (Scheme 2, Table 1).
˚
2.7088(3) A) being longer than the Pd1–I distance trans to
˚
the phosphine ligand (Pd1–I1 2.6566(3) A) (Fig. 4). There-
fore, the C6H4PPh3 group exerts a stronger trans-influence

H. Lang et al. / Journal of Organometallic Chemistry 691 (2006) 3834–3845
3839
2+
2OTf -
PPh3
Pd
PPh3
PPh3
Pd
PPh3
N
N (
)
13
2
I
N
N
I
I
Pd OTf
PPh3
toluene/CH2Cl2
PPh3
5
14a-14c
2+
2OTf-
PPh3
4+
4OTf-
25 ˚C
I
PPh3
Pd
PPh3
Ph3P
n
/ -hexane
CH2Cl2
Pd
Pd
+
Ph3P
N
N
Pd
PPh3
+ Pd +...
PPh3
PPh3
PPh3
I
Ph3P
11
15a, 15b
Scheme 2. Synthesis of 14a–14c and their conversion to 11, 15a and 15b, respectively.
Table 1
Synthesis of 14 and 15
the characteristic coupling pattern. Moreover, new reso-
nance signals were observed for the connecting units (1,4-
dicyano benzene: singlet at 7.03 ppm; 4,40-dicyano biphe-
nyl: two doublets at 6.73 and 7.68 ppm with JHH = 7.9 Hz;
4,40-bipyridine: two doublets at 7.03 and 8.13 ppm with
JHH = 6.5 Hz).
Compound
Yielda (%)
69
N
N
14a
14b
N
C
C N
The 31P{1H} NMR spectra of 14a–14c (d-chloroform)
show a singlet at ca. 20 ppm (Section 3).
80
80
25
27
In the IR spectra of 14a–14c one very characteristic
absorption at 1265 cmꢀ1 is found, which is consistent with
the non-coordinating character of OTfꢀ. A similar behav-
ior is observed for all other cationic organometallic species
discussed earlier. Furthermore, the C„N stretching vibra-
tion of 14a and 14b is a most informative spectroscopic
tool for monitoring the progress of the reaction of 5 with
13a and 13b, respectively. The mC„N band is thereby shifted
to higher wavenumbers (14a: 2269, 14b: 2260 cmꢀ1) as
compared to free 13a (2234 cmꢀ1) and 13b (2228 cmꢀ1).
This corresponds with the coordination of the cyano unit
to a transition metal atom, i.e. {[(dppp)Pd][C6H4-1,4-
(C„N)2]2(OTf)2}4 [20,21].
N
C
C N
14c
15a
N
N
N
C
C N
15b
N
C
C N
However, it appeared that 14a and 14b, which are much
better soluble than 14c, rearrange in dichloromethane–
hexane mixtures of ratio 2:3 to produce [trans-(Ph3P-
4-C6H4)(Ph3P)2Pd N\N ! Pd(PPh3)2(C6H4-4-PPh3)]4+
(15a, N\N = C6H4-1,4-(C„N)2; 15b, N\N = (C6H4-4-
C„N)2) along with {[(Ph3P-4-C6H4)(Ph3P)2Pd(l-I)]2}2+
(11) (Scheme 2). The formation of 11 and 15 from 14 is sim-
ilar to that already discussed earlier for 7/10 and 9/12 (Eqs.
(2) and (3)). The characterization of 15a and 15b is based
on IR and multinuclear NMR studies, whereby the same
analytical behavior is found as for 10 and 12 (vide supra
and Section 3).
a
Based on 5.
Subsequently, 0.5 equiv. of the Lewis-bases N\N (13a,
N\N = C6H4-1,4-(C„N)2; 13b, N\N = (C6H4-4-C„N)2;
13c, N\N = bipy) were added to 5, whereupon the bridged
bis-palladium complexes 14a–14c are formed (Scheme 2).
The latter species were identified by multinuclear NMR
spectroscopy and elemental analysis (Section 3). In com-
parison with 5, the resonance signals for the C6H4-I aro-
matic protons in the 1H NMR spectra of 14a–14c
(d-chloroform) are shifted upfield, both with retention of

3840
H. Lang et al. / Journal of Organometallic Chemistry 691 (2006) 3834–3845
Fig. 5. ORTEP plot (50% probability level) of 15b with the atom numbering scheme (the hydrogen atoms, two toluene molecules and the four OTfꢀ ions
are omitted for clarity; crystallographic C2 symmetry with symmetry operation ꢀx + 1, y + 1, ꢀz + 2). Symmetry generated atoms are indicated with the
˚
suffix A. Selected bond distances (A) and angles (ꢁ): Pd(1)–N(1) 2.082(5), Pd(1)–P(1) 2.334(2), Pd(1)–P(2) 2.338(2), Pd(1)–C(44) 1.993(5), N(1)–C(43)
1.142(8), C(62)–P(3) 1.802(8); and P(1)–Pd(1)–P(2) 173.03(6), N(1)–Pd(1)–C(44) 173.5(3), Pd(1)–N(1)–C(43) 174.1(7), N(1)–C(43)–C(37) 176.1(9).
Single crystals of 15b could be grown from diffusion of
toluene into a dichloromethane solution containing 15b
at 25 ꢁC. The asymmetric unit of 15b contains half of the
cationic part, two non-coordinated triflate ions and a sol-
vent molecule of toluene. In between the two phenylene
groups of the connecting 4,40-dicyanobiphenyl unit is a
center of inversion. The molecular structure of 15b is given
in Fig. 5 together with selected bond distances and angles.
The palladium atoms Pd1 and Pd1A display a distorted
square-planar coordination mode. As suggested from
NMR studies (Section 3) the triphenyl phosphine ligands
are positioned trans to each other, which automatically
positions the nitrogen donor atom of the bridging 4,40-dic-
yanobiphenyl trans to the C6H4 aryl ring of the C6H4PPh3
(d 0.00) with the solvent signal as reference signal. 31P{1H}
NMR were recorded at 101.202 MHz in CDCl3 with
P(OMe)3 as external standard (d 139.0, relative to 85%
H3PO4, d 0.00). Melting points were determined using ana-
lytically pure samples, sealed off in nitrogen-purged capil-
laries on a Gallenkamp MFB 595 010 melting point
apparatus. Microanalyses were performed by the Organic
Department at Chemnitz, University of Technology and
the Institute of Organic Chemistry at the University of
Heidelberg.
3.2. General remarks
Complex 2 [21] was prepared by a published procedure.
All other chemicals were purchased from commercial sup-
pliers and were used as received. For complexes 3, 7, 9–11,
12, 14 and 15 no 13C{1H} NMR data could be obtained,
since these species are less soluble in common NMR
solvents.
entity (Fig. 5). The phenylene moiety of the C6H4PPhþ
3
group is perpendicular oriented to the transition metal
coordination plane (87.1(2)ꢁ), while the biphenyl moiety
is in-plane bound (12.8(3)ꢁ). The Pd–N, Pd–P and Pd–C
separations are in the typical range as for other palladium
organometallic complexes [15].
3. Experimental part
3.3. Synthesis of 3
3.1. General methods
To 1,4-diiodobenzene (1) (900 mg, 2.73 mmol) dissolved
in 50 mL of toluene one equivalent of Pd(PPh3)4 (2) (3.15 g,
2.73 mmol) was added in one portion at 25 ꢁC. During 2 h
of stirring at this temperature a white precipitate formed.
The supernatant layer was decanted and the residue was
washed twice with n-hexane (2 · 20 mL) to gave trans-
(Ph3P)2Pd(I)(C6H4-4-I) (3) as a colorless solid (2.4 g,
2.50 mmol, 92% based on 1).
M.p.: 188 ꢁC (dec.). Anal. Calc. for C42H34I2P2Pd
(960.91): C, 52.50; H, 3.57. Found: C, 52.64; H, 3.80%.
IR (KBr): 3047 (m), 2961 (m), 1479 (s), 1461 (s), 1433
(vs), 1401 (sh), 1364 (m), 1262 (m), 1182 (s), 1093 (vs),
All reactions were carried out in an atmosphere of puri-
fied nitrogen (O2 traces: CuO catalyst, BASF AG, Ludwig-
shafen, Germany; H2O traces: molecular sieve, 4 A, Roth
˚
company) using standard Schlenk techniques. Solvents
were purified by distillation (n-hexane and dichlorometh-
ane: calcium hydride; toluene: sodium). FT-IR spectra
were recorded with a Perkin–Elmer FT-IR 1000 spectrom-
eter as KBr pellets. NMR spectra were recorded with a
Bruker Avance 250 spectrometer, operating in the Fourier
transform mode. 1H NMR spectra were recorded at
250.123 MHz (internal standard, relative to CDCl3, d
7.26 and CD2Cl2, d 5.32); 13C{1H} NMR spectra were
recorded at 67.890 MHz (internal standard, relative to
CDCl3, d 77.16 and CD2Cl2, d 53.50). Chemical shifts are
reported in d units (ppm) downfield from tetramethylsilane
1067 (s), 998 (vs), 784 (s), 740 (s), 691 (vs), 511 (vs) cmꢀ1
.
1H NMR (CDCl3): d = 6.2 (dd, 2H, JHH = 8.2 Hz,
o
4JHP = 3.8 Hz, H, C6H4), 6.4 (d, 2H, JHH = 8.2 Hz, mH,
C6H4), 7.2–7.3 (m, 18H, o/pH, PPh3), 7.4–7.5 (m, 12H,
mH, PPh3). 31P{1H} NMR (CDCl3): d = 21.9.

H. Lang et al. / Journal of Organometallic Chemistry 691 (2006) 3834–3845
3841
3.4. Synthesis of 7
M.p.: 135 ꢁC (dec.). Anal. Calc. for C66H53F6N2O6-
P3PdS2 Æ C6H6 (1332.81): C, 59.48; H, 4.01; N, 2.10. Found:
C, 59.71; H, 4.04; N, 1.75%. IR (KBr): 3057 (s), 1552 (m),
1436 (s), 1268 (vs) [ms(SO)], 1152 (s), 1108 (s), 1030 (s) [mCꢀF],
1001 (m), 804 (m), 729 (s), 692 (s), 637 (s), 528 (s) cmꢀ1. 1H
[AgOTf] (4) (50.0 mg, 0.195 mmol) was added in one
portion to 3 (186.9 mg, 0.195 mmol) which was dissolved
in
a toluene–dichloromethane mixture of ratio 5:2
o
(40 mL) at 25 ꢁC. After 30 min of stirring, the reaction mix-
ture was filtered through a pad of Celite. Pyrazine (6)
(15.6 mg, 0.195 mmol) was added in one portion to the
reaction solution, and the resulting suspension was stirred
for additional 30 min. After addition of 50 mL of n-hexane
a colorless precipitate formed. The solvents were removed
by filtration through Celite and the solid was dried in oil-
pump vacuum. Yield: 144.8 mg (0.136 mmol, 70% based
on 3).
NMR (CD2Cl2): d = 6.6 (m, 2H, H, C6H4PPh3), 6.7 (m,
2H, mH, C6H4PPh3), 6.8 (m, 2H, oH, C6H4N2), 7.3–7.4
(m, 45H, PPh3), 7.8 (m, 2H, mH, C6H4N2). 31P{1H}
NMR (CDCl3): d = 21.4, 27.3.
3.7. Synthesis of 11
Filtration of the supernatant solutions of 10, 9a/9b, 15a
or 15b through Celite and concentration in oil-pump vac-
uum gave colorless 11 (for example, 12 mg, 0.005 mmol,
5% based on 7; vide supra).
M.p.: 121 ꢁC (dec.). Anal. Calc. for C47H38F3I-
N2O3P2PdS (1063.16): C, 53.10; H, 3.60; N, 2.63. Found:
C, 53.55; H, 4.00; N, 2.54%. IR (KBr): 3052 (m), 2286
(w), 1480 (s), 1463 (s), 1435 (s), 1264 (vs) [ms(SO)], 1223
(sh), 1156 (s), 1097 (s), 1065 (s), 1029 (s) [mCꢀF], 993 (s),
820 (m), 797 (s), 748 (s), 694 (s), 636 (s), 573 (m), 518
M.p.: 152–153 ꢁC (dec.). Anal. Calc. for C86H68F6I2O6-
P4Pd2S2 Æ 0.5CH2Cl2 (2008.61): C, 51.43; H, 3.41. Found:
C, 51.38; H, 3.83%. IR (KBr): 2919 (m), 1627 (m), 1549
(m), 1483 (m), 1439 (s), 1400 (s), 1265 (vs) [ms(SO)], 1150
(s), 1107 (m), 1030 (s) [mCꢀF], 850 (m), 729 (s), 691 (s),
1
o
(vs) cmꢀ1. H NMR (CDCl3): d = 6.3 (m, 2H, H, C6H4),
6.7 (m, 2H, mH, C6H4), 7.0 (m, 2H, H, C4H4N2), 7.3–7.4
636, 529 (s) cmꢀ1. H NMR (CD2Cl2): d = 6.8 (m, 4H,
o
1
(m, 30H, PPh3), 8.2 (m, 2H, mH, C4H4N2). 31P{1H}
oH, C6H4PPh3), 7.3–7.7 (m, 64H, mH, C6H4PPh3 and
NMR (CDCl3): d = 21.2.
PPh3). 31P{1H} NMR (CD2Cl2): d = 21.5, 27.1.
3.5. Synthesis of 9a/9b
3.8. Synthesis of 12a/12b
To 3 (222.5 mg, 0.23 mmol) dissolved in 40 mL of tolu-
ene–dichloromethane (ratio 5:2) one equivalent of [AgOTf]
(4) (59 mg, 0.23 mmol) was added in one portion at 25 ꢁC.
After 30 min of stirring, the reaction mixture was filtered
through a pad of Celite. iso-Nicotinonitrile (8) (23 mg,
0.095 mmol) was added at 25 ꢁC, and the resulting suspen-
sion was stirred for 30 min. After appropriate work-up (see
synthesis of 7), 9a/9b were obtained as colorless solids.
Yield: 200 mg (0.184 mmol, 80% based on 3).
Complexes 9a/9b were dissolved in 5 mL of dichloro-
methane and 30 mL of toluene were added as a second
layer. After three days crystals of 12a/12b were obtained.
The supernatant solution was decanted and the colorless
crystals were hand-picked and dried in oil-pump vacuum.
Yield: 80 mg (0.031 mmol, 27% based on 9a/9b).
M.p.: 88 ꢁC (dec.). Anal. Calc. for C68H53F6N2O6-
P3PdS2.CH2Cl2 (1371.64): C, 59.55; H, 3.90; N, 2.04.
Found: C, 59.69; H, 4.13; N, 1.77%. IR (KBr): 3052 (m),
2276 (w), 2188 (w), 1970 (w), 1893 (w), 1606 (m), 1542
(m), 1481 (s), 1464 (s), 1435 (s), 1265 (vs) [ms(SO)], 1259
(vs), 1223 (s), 1152 (vs), 1097 (vs), 1066 (s), 1029 (s) [mCꢀF],
993 (vs), 836 (m), 795 (s), 749 (vs), 693 (vs), 637 (vs), 571
M.p.: 145 ꢁC (dec.). Anal. Calc. for C49H38F3IN2O3P2-
PdS (1087.18): C, 54.13; H, 3.52; N, 2.58. Found: C,
53.76; H, 3.87; N, 2.50%. IR (KBr): 3053 (s), 2375 (w),
2276 (w) [mC„N], 2244 [mC„N], 1972 (w), 1899 (w), 1822
(w), 1607 (m), 1479 (s), 1434 (s), 1367(w), 1264 (vs) [ms(SO)],
1154 (s), 1097 (s), 1066 (m), 1029 (vs) [mCꢀF], 993 (vs), 839
(w), 796 (m), 747 (vs), 696 (vs), 637 (vs), 515 (vs) cmꢀ1. 1H
1
(m), 521 (vs) cmꢀ1. H NMR (CDCl3): d = 6.3 (m, 2H,
oH, C6H4PPh3), 6.6 (m, 2H, mH, C6H4CN), 6.7 (d, 2H,
JHH = 7.5 Hz, mH, C6H4PPh3), 7.3–7.7 (m, 45H, PPh3),
o
o
NMR (CDCl3): d = 6.3 (d, 2H, JHH = 8.1 Hz, H, C6H4),
7.7 (d, 2H, JHH = 7.3 Hz, H, C6H4CN). 31P{1H} NMR
6.6 (m, 4H, mH, C6H4/oH, C5H4NCN), 7.2–7.4 (m, 30H,
PPh3), 8.5 (d, 2H, JHH = 6.2 Hz, mH, C5H4NCN).
31P{1H} NMR (CDCl3): d = 19.2, 21.2.
(CDCl3): d = 21.8, 27.9.
3.9. Synthesis of 14a
3.6. Synthesis of 10
Complex 3 (156 mg, 0.162 mmol) was dissolved in a
mixture of toluene–dichloromethane (ratio 5:2) (40 mL).
One equivalent of [AgOTf] (4) (41.7 mg, 0.162 mmol) was
added at 25 ꢁC. After stirring the reaction mixture for
30 min, it was filtered through a pad of Celite. To the elu-
ate, terephthalonitrile (13a) (10.4 mg, 0.081 mmol) was
added and the resulting suspension was stirred for addi-
tional 30 min. On addition of 50 mL of n-hexane a colorless
precipitate formed. The supernatant solution was decanted
Compound 7 (150 mg, 0.141 mmol) was dissolved in
5 mL of dichloromethane at 25 ꢁC and 30 mL of benzene
were added as a second layer. On slow diffusion of the
two layers during three days, complex 10 crystallized.
The supernatant solution was decanted, the remaining col-
orless crystals were hand-picked and dried in oil-pump vac-
uum. Yield: 60 mg (0.044 mmol, 32% based on 7).

3842
H. Lang et al. / Journal of Organometallic Chemistry 691 (2006) 3834–3845
and the residue was dried in oil-pump vacuum. Yield:
117.3 mg (0.056 mmol, 69% based on 3).
JHH = 8.0 Hz, mH, C6H4), 7.0 (d, 4H, JHH = 6.5 Hz, mH,
C6H5N), 7.2–7.4 (m, 60H, PPh3), 8.1 (d, 4H, JHH = 6.5 Hz,
oH, C6H5N). 31P{1H} NMR (CDCl3): d = 19.9.
M.p.: 120 ꢁC (dec.). Anal. Calc. for C94H72F6I2-
N2O6P4Pd2S2 (2094.28): C, 53.91; H, 3.47; N, 1.34. Found:
C, 54.37; H, 3.34; N, 1.33%. IR (KBr): 2926 (w), 2269 (m)
[mC„N], 1623 (m), 1480 (w), 1435 (s), 1401 (sh), 1265 (vs)
[ms(SO)], 1151 (s), 1096 (m), 1067 (w), 1029 (s) [mCꢀF], 994
3.12. Synthesis of 15a
Compound 14a (200 mg, 0.095 mmol) was dissolved in
5 mL of dichloromethane at 25 ꢁC and 30 mL of benzene
were added as a second layer. Single crystals of 15a grow
during five days. The supernatant solution was decanted
and the colorless crystals were hand-picked and dried in
oil-pump vacuum. Yield: 70 mg (0.026 mmol, 28% based
on 14a).
1
(m), 797 (s), 749 (s), 693 (s), 636 (s), 519 (s) cmꢀ1. H
NMR (CDCl3): d = 6.3 (dd, 4H, JHH = 8.1 Hz,
o
4JHP = 3.6 Hz, H, C6H4), 6.7 (d, 4H, JHH = 8.1 Hz, mH,
C6H4), 7.0 (s, 4H, C6H4CN), 7.3–7.4 (m, 60H, PPh3).
31P{1H} NMR (CDCl3): d = 21.0.
3.10. Synthesis of 14b
M.p.: 165 ꢁC (dec.). Anal. Calc. for C132H102F12N2O12-
P6Pd2S4 (2663.19): C, 59.53; H, 3.86; N, 1.05. Found: C,
59.44; H, 4.19; N, 0.96%. IR (KBr): 2997 (s), 2290 (m)
[mC„N], 1637 (m), 1586 (m), 1552 (s), 1481 (s), 1437 (s),
1378 (m), 1267 (vs) [ms(SO)], 1223 (s), 1191 (m), 1151 (s),
1109 (s), 1049 (m), 1031 (s) [mCꢀF], 998 (m), 804 (m), 731
[AgOTf] (4) (59 mg, 0.23 mmol) was added in one por-
tion to 3 (222.5 mg, 0.23 mmol) which was dissolved in a
mixture of toluene–dichloromethane in the ratio of 5:2
(40 mL) at 25 ꢁC. After 30 min of stirring, the reaction mix-
ture was filtered through a pad of Celite. To the eluate
was added 4,40-biphenyldicarbonitrile (13b) (23 mg,
0.095 mmol), and stirring was continued for 30 min. Addi-
tion of 50 mL of n-hexane afforded a colorless precipitate.
The supernatant solution was removed by filtration and the
residue was dried in oil-pump vacuum. Yield: 200 mg
(0.089 mmol, 80% based on 3).
(s), 692 (s), 637 (s), 547 (sh) cmꢀ1 1H NMR (CDCl3):
.
d = 6.8 (m, 8H, C6H4PPh3), 7.3–7.9 (m, 90H, PPh3), 7.8
(m, 4H, C6H4-1,4-(CN)2). 31P{1H} NMR (CDCl3):
d = 21.4, 27.3.
3.13. Synthesis of 15b
M.p.: 127 ꢁC (dec.). Anal. Calc. for C100H76F6I2-
N2O6P4Pd2S2 Æ CH2Cl2 (2255.31): C, 53.23; H, 3.40; N,
1.24. Found: C, 54.30; H, 3.86; N, 1.60%. IR (KBr): 3057
(s), 2260 (m) [mC„N], 1602 (m), 1482 (s), 1436 (s), 1364
(w), 1399(m), 1268 (vs) [ms(SO)], 1224 (sh), 1154 (s), s 1096
(s), 1067 (m), 1030 (vs) [mCꢀF], 994 (vs), 826 (s), 796 (s),
Compound 14b (200 mg, 0.094 mmol) was dissolved in
5 mL of dichloromethane at 25 ꢁC and 30 mL of benzene
were added as a second layer. During 5 days single crystals
of 15b formed. After decanting the supernatant solution,
the crystals were hand-picked and dried in oil-pump vac-
uum. Yield: 80 mg (0.028 mmol, 30% based on 14b).
M.p.: 146 ꢁC (dec.). Anal. Calc. for C145H122F12N2-
O12P6Pd2S4 (2839.49): C, 61.51; H, 4.06; N, 0.99. Found:
C, 60.77; H, 4.18; N, 1.35%. IR (KBr): 3056 (m), 2907
(s), 2280 (m) [mC„N], 1553 (m), 1432 (s), 1269 (vs) [ms(SO)],
1223 (s), 1145 (s), 1030 (s) [mCꢀF], 801 (s), 796 (s), 695 (s)
749 (vs), 694 (vs), 637 (vs), 518 (vs) cmꢀ1
.
1H NMR
o
(CDCl3): d = 6.3 (bd, 4H, JHH = 7.5 Hz, H, C6H4), 6.6
(d, 4H, JHH = 7.5 Hz, mH, C6H4), 6.7 (d, 4H, JHH = 7.9 Hz,
mH, C6H4CN), 7.3–7.9 (m, 60H, PPh3), 8.8 (d, 4H, JHH
=
o
7.9 Hz, H, C6H4CN). 31P{1H} NMR (CDCl3): d = 21.1.
1
cmꢀ1. H NMR (CDCl3): d = 6.3 (dd, 4H, JHH = 7.5 Hz,
o
3.11. Synthesis of 14c
4JHP = 3.7 Hz, H, C6H4PPh3), 6.6 (d, 4H, JHH = 7.5 Hz,
mH, C6H4CN), 6.7 (d, 4H, JHH = 7.6 Hz, mH, C6H4PPh3),
7.3–7.7 (m, 90H, PPh3), 7.7 (d, 4H, JHH = 7.6 Hz, oH,
C6H4CN). 31P{1H} NMR (CDCl3): d = 21.8, 21.9.
To 3 (201.2 mg, 0.21 mmol) dissolved in 40 mL of tol-
uene–dichloromethane (ratio 5:2) one equivalent of 4
(53.8 mg, 0.21 mmol) was added at 25 ꢁC. After 30 min
of stirring at this temperature, the reaction mixture was
filtered through a pad of Celite. To the eluate 4,40-bipyri-
dine (13c) (16.3 mg, 0.105 mmol) was added in one por-
tion and the resulting suspension was stirred for 30 min.
After appropriate work-up (see synthesis of 14a), complex
14c was obtained as a colorless solid. Yield: 200 mg
(0.094 mmol, 80% based on 3).
4. X-ray structure determination
The solid-state structures of 3, 9a, 10, 11 and 15b were
determined by single-crystal X-ray diffraction. For data
collection a Bruker Smart 1k CCD diffractometer with
graphite monochromatized Mo Ka radiation (k =
˚
0.71073 A) was used. Crystallographic data are given in
M.p.: 158 ꢁC (dec.). Anal. Calc. for C96H76F6I2N2O6P4-
Pd2S2 (2122.33): C, 54.33; H, 3.61; N, 1.32. Found: C,
53.85; H, 4.03; N, 1.40%. IR (KBr): 2963 (s), 2929 (m),
2858 (m), 1654 (m), 1478 (m) 1432 (s), 1400(s), 1261 (vs)
[ms(SO)], 1094 (sh), 1026 (vs) [mCꢀF], 801 (vs), 740 (s), 691
Table 2. For protection against oxygen and moisture the
preparation of single crystals was performed in perfluoro
alkyl ether (ABCR GmbH & Co KG; viscosity 1600 cSt).
Data collection and cell determination has been done with
the program SMART [22,23]. For data integration and refine-
ment of the unit cell the program SAINT was used [23]. The
space group was determined using the program XPREP [23]
1
(vs), 637 (m) cmꢀ1. H NMR (CDCl3): d = 6.5 (dd, 4H,
4
JHH = 8.0 Hz, JHP = 3.2 Hz, oH, C6H4), 6.8 (d, 4H,

H. Lang et al. / Journal of Organometallic Chemistry 691 (2006) 3834–3845
3843
Table 2
Summary of crystallographic data for 3, 9a, 10, 11, and 15b
3
9a
10
11
15b
Formula
C42H34I2P2Pd
C50H39Cl3N2F3IP2O3PdS C69H56F6N2P3O6PdS2 C90H72Cl12F6I2P4O6-
Pd2S2
C152H122F12N2P6O12
Pd2S4
-
Formula weight
Space group
Crystal system
Z
960.83
I2/a
1206.48
1386.59
P21/n
2443.48
2923.38
P21/n
ꢀ
ꢀ
P1
P1
Monoclinic
4
11.431(6)
13.423(7)
23.570(15)
90
95.131(9)
90
3600(1)
1.772
Triclinic
2
Monoclinic
4
11.1031(5)
18.5170(8)
31.2694(13)
90
98.0750(10)
90
6365.1(5)
1.447
Triclinic
1
Monoclinic
2
17.630(2)
21.776(2)
18.791(3)
90
103.760(2)
90
7007.1(16)
1.386
˚
a (A)
11.0850(13)
14.5885(17)
16.876(2)
85.705(2)
85.651(2)
73.064(2)
2599.2(5)
1.542
13.2529(4)
13.5826(5)
15.2062(5)
85.8510(10)
75.9520(10)
66.6700(10)
2437.41(14)
1.665
˚
b (A)
˚
c (A)
a (ꢁ)
b (ꢁ)
c (ꢁ)
Volume (A )
dcalc (g cmꢀ1
3
˚
)
Temperature (K)
F(000)
203(2)
1872
2.348
298(2)
1200
1.259
0.4 · 0.2 · 0.2
1.85, 25.35
ꢀ13, ꢀ17, 0; 13, 17, 20
103(2)
2836
0.504
193(2)
1208
1.502
0.4 · 0.3 · 0.3
1.38, 28.38
ꢀ16,ꢀ18,0; 17,18,20
203(2)
2996
0.462
0.3 · 0.2 · 0.2
1.51, 26.47
ꢀ22,0,0; 21,27,23
l (Mo Ka) (mmꢀ1
Crystal size (mm)
hmin, hmax (ꢁ)
)
0.3 · 0.2 · 0.2
1.73, 26.37
ꢀ14, 0, 0; 14, 16, 29
0.52 · 0.03 · 0.03
1.88, 28.28
ꢀ14,0,0; 14,24,41
h,k,l (min, max)
No. of total, unique
22516, 3840 (0.1147) 19795, 10527 (0.0605)
48973, 15781 (0.0683) 19060, 11995 (0.0247) 47795, 14794 (0.0827)
reflections (Rav
Nref, Npar
)
3676, 215
9397, 708
15781, 1030
0.0533, 0.0984
0.1224, 0.1469
1.038
11995, 559
0.0368, 0.0520
0.0870, 0.0931
1.042
14362, 898
0.0847, 0.1351
0.1993, 0.2254
1.049
a
R1 (I > 2rI, all)
0.0769, 0.1004
0.1901, 0.2047
0.970
0.0685, 0.1082
0.1656, 0.1951
1.031
ꢀ1.279, 1.360
b
wR2 (I > 2rI, all)
S
3
˚
Residual density (e/A ) ꢀ2.271, 4.058
ꢀ0.836, 1.706
ꢀ0707, 0.905
ꢀ0.711, 2.058
P
kF ojꢀjF c
k
a
P
R1 ¼
.
jF o
j
rffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi
P
2
wðF 2oꢀF 2c
Þ
ðmaxðF 2o;0Þþ2F 2c
Þ
.
b
1
P
wR2 ¼
with w ¼
Þþðg PÞ þg P; P ¼
2
2
wðF 2o
Þ
r2ðF 2o
3
1
2
and the absorption has been corrected empirically with
SADABS [24]. The structure was solved by direct methods
with the program SHELX 97 and structure refinement was
based on least-square based F2 using SHELX 97 [25].
All non-hydrogen atoms were fully refined anisotropi-
cally in their local positions. The positions of the hydrogen
atoms in 3, 9a, 11 and 15b have been refined with a riding
model. In 10 the hydrogen atom positions of the main mol-
ecule have been taken from the difference Fourier map and
refined freely. Others have been refined with a riding
model.
In 9a the chloroform and the triflate counter anion are
disordered and have been refined to split occupancies of
0.52/0.16/0.32 (HCCl3), 0.75/0.25 (SO3) and 0.33/0.67
(CF3), respectively. In 15b the toluene solvent molecule is
disordered and has been refined to a split occupancy of
0.42/0.58.
15b. Copies of this information may be obtained free of
charge from The Director, CCDC, 12 Union Road, Cam-
bridge, CB2 1EZ UK, fax +44 1223 336033; e-mail: depos-
it@ccdc.cam.ac.uk or www: http://www.ccdc.cam.ac.uk.
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