Thioether- and selenoether-carboxylates in palladium chemistry: Conclusive proof of hemilabile properties of O-Se ligands

Article abstract of DOI:10.1016/S0022-328X(00)00571-4

Reaction of trans-[PdCl(Ph)(PPh₃)₂] with the thallium salts R-X-(CH₂)_n-COOTl (n=1, X=S, R=Me, Et, i-Pr, t-Bu, Ph; n=1, X=Se, R=Me, Ph; n=2, X=S, R=Et, Ph) yields the compounds trans-[Pd(OOC-(CH₂)_n-X-R-κ¹-O)Ph(PPh ₃)₂] (1a-1i). In solution, complexes 1a-1i participate in hemilabile equilibria in which one PPh₃ ligand is replaced by a sulphur/selenium atom of the ligand to afford the O-S/Se chelates under certain circumstances. Solid state structures of the monodentate complex 1h as well as its corresponding chelate (2h) together with the NMR observation of both species in solution, conclusively prove the hemilabile properties of this O-Se ligand. Depending on the size of the substituent on the potential sulphur or selenium donor atom, however, a PPh₃ ligand is not always displaced upon donor atom coordination. In such equilibria no free PPh₃ is detected and a five-coordinate square pyramidal structure is proposed for the O-S/Se chelate. The position of the relevant equilibrium depends on both the basicity of the potential sulphur or selenium donor atom as well as on the polarity of the solvent.

Full text of DOI:10.1016/S0022-328X(00)00571-4

www.elsevier.nl/locate/jorganchem
Journal of Organometallic Chemistry 619 (2001) 164–178
Thioether- and selenoether-carboxylates in palladium chemistry:
conclusive proof of hemilabile properties of O–Se ligands
Matthias W. Esterhuysen a, Robert Bru¨ll a, Helgard G. Raubenheimer a,*,
Catharine Esterhuysen a, Gert J. Kruger b
a Department of Chemistry, Uni6ersity of Stellenbosch, Pri6ate Bag X1, Matieland 7602, South Africa
b Department of Chemistry and Biochemistry, P.O. Box 524, Auckland Park, Johannesburg 2006, South Africa
Received 21 December 1999; accepted 18 August 2000
Dedicated to Professor Dr Dr hc Wilhelm Keim on the occasion of his 65th birthday.
Abstract
Reaction of trans-[PdCl(Ph)(PPh3)2] with the thallium salts R–X–(CH2)n–COOTl (n=1, X=S, R=Me, Et, i-Pr, t-Bu, Ph;
n=1, X=Se, R=Me, Ph; n=2, X=S, R=Et, Ph) yields the compounds trans-[Pd(OOC–(CH2)n–X–R–k1-O)Ph(PPh3)2]
(1a–1i). In solution, complexes 1a–1i participate in hemilabile equilibria in which one PPh3 ligand is replaced by a sulphur/sele-
nium atom of the ligand to afford the O–S/Se chelates under certain circumstances. Solid state structures of the monodentate
complex 1h as well as its corresponding chelate (2h) together with the NMR observation of both species in solution, conclusively
prove the hemilabile properties of this O–Se ligand. Depending on the size of the substituent on the potential sulphur or selenium
donor atom, however, a PPh3 ligand is not always displaced upon donor atom coordination. In such equilibria no free PPh3 is
detected and a five-coordinate square pyramidal structure is proposed for the O–S/Se chelate. The position of the relevant
equilibrium depends on both the basicity of the potential sulphur or selenium donor atom as well as on the polarity of the solvent.
© 2001 Elsevier Science B.V. All rights reserved.
Keywords: Palladium; Arylpalladium complexes; Hemilability; Oxygen–selenium ligands; Oxygen–sulphur ligands
processes where it is currently believed that the dissoci-
ation of the chelate ring to create one free coordination
position is initiated ‘on demand’ by either substrate
monomers or coordinating solvent molecules [3]
(Scheme 1).
While the hemilabile behaviour of P–O ligands has
been well investigated and substantiated by spectro-
scopic methods [1,3,5], much less is known about po-
tentially hemilabile P–N [6–9], P–S [10,11], O–N
[12–14], O–O [13] and O–S [13] ligands. The hemi-
labile properties of a few thioethercarboxylate ligands
in palladium chemistry have recently been investigated
1. Introduction
Recent studies in coordination chemistry have shown
considerable interest in the use of so-called hemilabile
ligands [1]. Hemilabile ligands generally have at least
two different potential donor atoms, e.g. phosphorus
and oxygen, enabling the formation of complexes in
which one donor atom is strongly bonded whilst the
other is more loosely coordinated [2]. According to the
generally accepted theory, the latter donor atom can
dissociate from the metal so that the ligand binds in a
monodentate mode, vacating a coordination site for a
potential substrate [3,4]. Palladium complexes with
hemilabile ligands are known to exhibit interesting cat-
alytic properties, especially in C–C bond formation
* Corresponding author. Tel.: +27-21-8083850; fax: +27-21-
8083849.
E-mail address: hgr@land.sun.ac.za (H.G. Raubenheimer).
Scheme 1. Availability of a free coordination position with hemilabile
P–O ligands.
0022-328X/01/$ - see front matter © 2001 Elsevier Science B.V. All rights reserved.
PII: S0022-328X(00)00571-4

M.W. Esterhuysen et al. / Journal of Organometallic Chemistry 619 (2001) 164–178
165
in our group [15]. The work focused on hemilabile
equilibria in which neutral sulphur atoms in monoden-
tately, oxygen-bonded ligands coordinate to palladium
while replacing a triphenylphosphine ligand. These sub-
stitutions were studied in solution by means of 31P{1H}-
NMR spectroscopy and the subsequent hemilabile
equilibria could be observed by peak broadening. Crys-
tallization, however, failed to produce the proposed
bidentate O–S chelates and only the oxygen-bonded
complexes were isolated.
amounts (B5%) of dark-yellow crystals amongst
colourless crystals of 1a and 1h. Elemental analyses as
well as single crystal X-ray diffraction studies identified
these compounds as the O–S/Se chelate complexes 2a
and 2h (Figs. 4 and 6). In both compounds a coordi-
nated sulphur/selenium group substituted a phosphine
ligand.
2.2. P{1H}-NMR spectroscopic characterization of
complexes 1a–1i
The aim of the current work was not only to extend
the knowledge concerning the occurrence of hemilabile
equilibria, but also to isolate and structurally character-
ize the postulated coordination types in such equilibria.
In this paper we thus describe a continuation and
extension of the above-mentioned study involving the
synthesis and characterization of phenylpalladium com-
pounds bearing alkyl and aryl thioethercarboxylate O–
S-type, as well as alkyl- and aryl-selenoethercarboxylate
O–Se-type, ligands. Molecular structures of O–S/Se
ligated complexes, showing the potentially bidentate
ligands in both monodentate and bidentate bonding
modes, are presented. Solid state structures of the
monodentate complex 1h as well as its resulting chelate
(2h), together with the observation that they are in
equilibrium when dissolved conclusively prove the
hemilabile properties of this O–Se ligand in solution.
Furthermore, different hemilabile behaviour for sul-
phur- and selenium-donor atom coordination to palla-
dium observed spectroscopically in solution, is
presented. The effect of chelate ring size has also been
investigated.
The diphosphine complexes 1a–1i all exhibit NMR
signals for coordinated PPh3 ligands in their room
temperature 31P{1H}-NMR spectra (CDCl3). These
peaks appear at l 21.5 for 1c, 1d and 1h and their
broadness suggests the presence of dynamic phenomena
(Section 3). In addition, the same complexes each ex-
hibit equally broad peaks for free PPh3 at approxi-
mately l −4.7, and another similarly broad peak with
roughly the same intensity at l 25.2, 26.0 and 27.3 (Fig.
1) corresponding to coordinated PPh3 in the formed
chelates. For 1h the latter two peaks appear only at low
temperature (−40°C) as the exchange rate is too fast
for the NMR instrument to distinguish between the
species involved in the equilibrium (Scheme 3) at higher
temperatures.
2. Results and discussion
2.1. Synthesis of
bis(triphenylphosphine)phenylpalladium(II) complexes
with hemilabile O–S and O–Se ligands
The new phenylpalladium complexes 1a–1i were pre-
pared by the general procedure outlined in Scheme 2.
Precipitation of TlCl with excess thallium salt of a
ligand drove the reaction. The complexes 1a, 1b, 1e, 1h,
1i were isolated in good and 1c, 1d, 1f, 1g in moderate
yields by crystallization from THF/pentane. Characteri-
zation data for all the new compounds appear in Sec-
tion 3. As a result of the dynamic equilibria observed it
was not always possible to assign all the signals in the
13C{1H}-NMR spectra.
Scheme 2. Preparation of phenylpalladium(II) compounds 1a–1i.
The crystal and molecular structures of 1a and its
selenium analogue 1h were determined by single crystal
X-ray diffraction and they clearly exhibited uncoordi-
nated sulphur and selenium atoms (Figs. 3 and 5).
Prolonged crystallization from THF/pentane or ben-
zene/pentane at low temperatures yielded small
Scheme 3. Hemilabile equilibrium with PPh3 exchange.

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M.W. Esterhuysen et al. / Journal of Organometallic Chemistry 619 (2001) 164–178
Fig. 1. Variable temperature 31P{1H}-NMR spectra of 1c exhibiting hemilabile equilibrium.

M.W. Esterhuysen et al. / Journal of Organometallic Chemistry 619 (2001) 164–178
167
The room temperature 31P{1H}-NMR spectra
(CDCl3) of 1a, 1b, 1e, 1f, 1g and 1i also exhibit
extremely broad peaks (up to 14 ppm wide for 1b).
However, no free PPh3 is indicated in any of these
spectra. Resonances, probably due to PPh3 in O–S
chelated species at l 23.9 appear downfield from the
signals for PPh3 in the non-chelated species in the
spectra of 1f and 1g. For complexes 1a, 1b, 1e and 1i
only one very broad signal is observed at l 22.5, 22.0,
21.5 and 23.0, representing PPh3 in the chelated and
non-chelated species involved in the equilibria. With
C6D6 as solvent these peaks sharpen, indicating slower
exchange rates. For example 1e, 1f and 1g exhibit well
defined room temperature signals for PPh3 in the O–S
chelated species at l 25.7, 23.3 and 23.2. For 1a, 1b and
1i, however, only a single broad signal is still present.
Cooling the NMR samples (CDCl3) of 1a and 1b down
to −60°C enabled the observation of 31P{1H}-NMR
Fig. 2. Variable temperature 31P{1H}-NMR spectra of 1a.

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M.W. Esterhuysen et al. / Journal of Organometallic Chemistry 619 (2001) 164–178
signals at l 27.5 (Fig. 2) and 26.6 for PPh3 probably in
a chelated species participating in a non-substitutive
equilibrium.
2.4. Crystal and molecular structures of 1a, 1h, 2a and
2h
The absence of free PPh3, together with the presence
of signals for PPh3 in a new species in the equilibria of
1a, 1b, 1e, 1f and 1g, appearing downfield from the
signals for PPh3 in the non-chelated species, indicates
that these complexes probably participate in a associa-
tive hemilabile equilibrium but that the S or Se coordi-
nation is not accompanied by PPh3 substitution
(Scheme 4). An 18e− five-coordinate square pyramidal
structure of type 3 is plausible. Ab initio and empirical
calculations are currently being undertaken in an effort
to strengthen our postulate. Although 18e− five-coordi-
nate square pyramidal structures have been proposed as
transtion states during substitution reactions for many
organometallic palladium complexes [16–18], only one
example is known where this species could be isolated
and structrally characterized by X-ray diffraction [19].
The formation of 2a and 2h upon crystallization
instead of the spectroscopically observed species, 3a
and 3h, indicates that PPh3 substitution occurs during
crystal formation.
The molecular structures of complexes 1a, 1h, 2a and
2h are shown in Figs. 3–6. For clarity the disorder
exhibited by the carboxylate ligands in the crystal struc-
tures of 1a and 1h and the solvent inclusions found in
the structures of 1h, 2a and 2h are not shown in the
figures.
The molecular structures of the monodentate forms
1a and 1h on the one hand and the bidentate forms 2a
and 2h on the other hand closely resemble each other.
The bond lengths and angles observed for 1a and 1h are
the same within three standard deviations of the aver-
age, except for the expected differences between the two
S–C bond lengths in 1a and the Se–C bond lengths in
1h. The same is true for 2a and 2h with the bond
lengths and angles in the phenyl ligand and remaining
triphenylphosphine ligand (one triphenylphosphine lig-
and was lost upon coordination of the S/Se atoms) also
being very similar to their monodentate counterparts.
All four structures exhibit a square-planar configura-
tion around the Pd atom, which is slightly deformed in
2a and 2h as a result of the ring strain in the five-mem-
bered chelate rings (maximum deviations from planar-
2.3. Infrared spectroscopic characterization of
complexes 1a–1i
,
ity of 0.081(1) and 0.110(1) A respectively). Smaller
O(1)–Pd–S/Se angles are found in the type 2 structures
(83.9/84.9°) compared to the O(1)–Pd–P angles in
structures of type 1 (91.9/91.9° and 95.4/92.4° for
O(1)–Pd–P(1) and O(1)–Pd–P(2) in 1a and 1h respec-
tively). The positions of the oxygen atoms are more
affected by the ring strain and the C(4)–Pd–O(1) an-
gles in 2a and 2h deviate significantly from linearity
(170.9 and 170.0°), whereas the P–Pd–S/Se angles are
closer to linearity (175.3 and 174.2°). All the internal
ligand angles between atoms in the chelate ring are also
slightly larger than their non-chelated counterparts as a
result of the strain.
The phenyl ligand coordinated to the palladium is
twisted with respect to the plane through the Pd, P(1),
P(2), C(4) and O(1) atoms. In the non-chelated struc-
tures (1a and 1h) it is almost perpendicular to the plane
(88.6 and 88.9° away), while in the chelated structures
(2a and 2h) it is rotated by only 73.9° (2a) and 75.4°
(2h), presumably as a result of the extra space created
by the absence of the second triphenylphosphine ligand.
For structures 1a and 1h this effect can also be ob-
served in the carboxylate ligand, where O(1), C(1), O(2)
and C(2) form a plane which is nearly co-planar to the
phenyl ring (11.9 and 3.7° difference in 1a and 1h
respectively). There is, furthermore, an internal pseudo-
mirror plane through the phenyl ring and atoms O(1),
O(2) and C(1) of the carboxylate ligand in 1h, with the
disordered atoms related to each other across it.
In structures 2a and 2h the planar carboxylate lig-
ands are twisted at angles of 14 and 16° respectively to
The asymmetric w(CO) stretching vibrations for the
carboxyl group of the O–S/Se ligands in complexes
1a–1i are found between 1600 and 1628 cm−1, typi-
cally at lower energy than for the corresponding free
carboxylic acids. This can be ascribed to coordination
and partial electron loss from the carboxylate ligand to
palladium. A 21 cm−1 ‘red shift’ is observed between
the w(CO)as absorption bands going from 1a (1610
cm−1) to 2a (1631 cm−1) and from 1h (1600 cm−1) to
2h (1621 cm−1), indicating lower p-bond character of
the CꢀO-bond in the chelated compounds. The values
for w(CO)as also correspond to the positions of the
same vibrations in the palladium thioethercarboxylates
previously studied (1595–1608 cm−1) [15].
Scheme 4. Proposed equilibrium with no PPh3 exchange.

M.W. Esterhuysen et al. / Journal of Organometallic Chemistry 619 (2001) 164–178
169
the planes through P, S or Se, C(4) and O(1). The methyl
groups attached to the S or Se atoms (C(3)), however,
lie well above this plane.
In structures 2a and 2h the molecules pack in strings
with the chelate rings parallel but alternating in orienta-
tion and with solvent molecules (THF in 2a and benzene
in 2h) sandwiched in between the rings.
(R3=Me [27], Ph [28]) were prepared according to
literature methods. (Methylthio)acetic acid was pur-
chased from Aldrich and used without further purifica-
tion. Melting points were determined on a Bu¨chi 535
apparatus. NMR spectra (1H at 300 MHz, 13C{1H} at
75 MHz with Me4Si as internal standard and 31P{1H}-
NMR at 121 MHz with 85% H3PO4 as external standard)
were recorded on a Varian VXR 300 FT NMR spectrom-
eter. 77Se {1H}-NMR spectra (at 76 MHz with 20%
Se(CH3)2 in d1-chloroform as external standard) were
measured on a Bruker Avance DXR 400 FT NMR
spectrometer. NMR peaks are labelled as singlet (s),
doublet (d), triplet (t), multiplet (m) or broad (br). In
NMR spectra where more than one species is detected,
peaks are assigned to the proposed S or Se coordinated
and not coordinated compounds. FAB-MS was recorded
on a Micromass DG 70/70E mass spectrometer using
xenon gas as bombardment atoms. IR data (4000 to 600
cm−1, resolution 4 cm−1) were measured as KBr pellets
of recrystallized samples using a Perkin–Elmer 841 IR
spectrophotometer. Peaks are described as very strong
(vs), strong (s), medium (m) or weak (w) in intensity.
Elemental analyses were carried out by the Division of
Energy Technology, CSIR, Pretoria, South Africa.
3. Experimental
3.1. General, materials and measurement
Reactions and manipulations involving organometal-
lic compounds were carried out under a dry nitrogen
atmosphere using standard Schlenk and vacuum-line
techniques. All solvents, except methanol, were dried and
purified by conventional methods and freshly distilled
under nitrogen shortly before use. Other reagents were
used without further purification.
The palladium starting complex, trans-[Pd-
Cl(Ph)(PPh3)2] [20], and the ligands, R1S–CH2–COOH
(R1=Et [21], i-Pr [22], t-Bu [23], Ph [24]), R2S–(CH2)2–
COOH (R2=Et [25], Ph [26]) and R3Se–CH2–COOH
Fig. 3. ORTEP plot of the molecular structure of complex 1a (one of two disordered configurations), showing the numbering scheme.

170
M.W. Esterhuysen et al. / Journal of Organometallic Chemistry 619 (2001) 164–178
Fig. 4. ORTEP plot of the molecular structure of complex 2a, showing the numbering scheme.
3.2. Crystal structure determinations of 1a, 1h, 2a and
2h
and allowed anisotropic thermal displacement motion.
The disordered atoms in the carboxyl ligands of 1a and
1h were also located by difference Fourier mapping, and
refined individually, with all atoms except for the disor-
dered C1 and C2 sites in 1h given anisotropic thermal
displacement parameters. The disordered solvent
molecules in 1a, 1h and 2a were initially refined as rigid
bodies. The rigid body constraints were then lifted and
the bond lengths restrained to average literature dis-
tances listed in the International Tables for Crystallog-
raphy [32], during isotropic refinement. It was possible
to locate most of the non-solvent hydrogen atoms by
Fourier map.
SHELX-97 [33] was used to solve and refine the struc-
tures and to generate the tables. ORTEP-3 [34] was used
to generate the figures at 50% probability level. Final
values for the residuals of R, wR and S in 1a, 1h, 2a and
2h are listed in Table 1 together with crystal data,
refinement data and data collection parameters. Impor-
tant bond lengths and angles in 1a, 1h, 2a and 2h are
listed in Tables 2 and 3. Fractional coordinates and
equivalent isotropic displacement parameters of all
atoms in the respective structures are listed in Tables
4–7.
Crystals of 1a and 1h, suitable for X-ray crystallo-
graphic analysis, were obtained by crystallization from
THF/pentane. Prolonged crystallization of 1a and 1h
from THF/pentane, furthermore, yielded small amounts
of 2a and 2h among 1a and 1h. Diffraction data of 1a,
1h and 2a were collected on a Siemens SMART system
with CCD detector at room temperature, using graphite
monochromated Mo–Ka radiation. Empirical absorp-
tion corrections were applied using the Siemens utility
program SADABS for CCD detectors [29]. Diffraction
data of 2h were collected on a Philips PW1100 diffrac-
tometer, controlled by the program PWPC [30], at room
temperature using ꢀ–2q scans and graphite monochro-
mated Mo–Ka radiation. Data reduction and absorp-
tion corrections were performed with the XTAL3.4 suite
of programs (DIFDAT and ABSCAL) [31].
All structures were solved by interpretation of a
Patterson synthesis, which yielded the positions of the
metal atoms. The remaining non-hydrogen atoms were
found by difference Fourier map. Those atoms in non-
disordered sites were refined by full-matrix least-squares

M.W. Esterhuysen et al. / Journal of Organometallic Chemistry 619 (2001) 164–178
171
3
3.3. Preparation of
2.6 (br, 2H, CH2S), 6.88 (d, 2H, J 8.1 Hz, Pd–C6H5),
6.35 (t, 2H, 3J 7.5 Hz, Pd–C6H5), 6.52 (t, 1H, 3J 7.5 Hz,
Pd–C6H5), 7.0–7.5 (m, 30H, Pd–P(C6H5)3). 13C{1H}-
NMR l (d1-chloroform, 298 K): 16.2 (SCH3), 39.5
(CH2S), 122.3 (Pd–C6H5), 127.6 (Pd–C6H5), 128.3
(Pd–P(C6H5)3), 130.0 (Pd–P(C6H5)3), 131.3 (Pd–
C6H5), 135.0 (Pd–P(C6H5)3), 137.9 (Pd–P(C6H5)3),
148.6 (Pd–C6H5), 173.6 (Pd–OCO). 31P{1H} l (d1-chlo-
roform, 298 K): 20–25 (br). IR (KBr): was(CO) 1610
cm−1 (vs). FAB-MS: m/z 813 [M+]. Anal. Calc. for
C45H40P2PdO2S: C, 66.5; H, 5.0; S, 3.9. Found: C, 66.6;
H, 5.1; S, 3.8%.
trans-[Pd(OOC–CH2–SR–s1-O)Ph(PPh3)2] (1a
R=Me; 1b R=Et; 1c R=i-Pr; 1d R=t-Bu; 1e
R=Ph)
To a solution of RS–CH2–COOH (0.48 mmol, R=
Me, Et, i-Pr, t-Bu, Ph) in 15 ml methanol was added
113 mg (0.24 mmol) Tl2CO3. The solution was stirred at
room temperature until all the Tl2CO3 dissolved, after
which the solvent was removed in vacuo. The remain-
ing thallium salt was dried for a further 30 min in
vacuo and subsequently manipulated under nitrogen.
The thallium salt was suspended in 15 ml THF and
after adding trans-[PdCl(Ph)(PPh3)2] (200 mg, 0.27
mmol) the mixture was stirred for 12 h at room temper-
ature. Precipitated TlCl and unreacted thallium salts
were filtered off through a Celite pad. The volume of
the colourless to light red solutions was reduced in
vacuo to approximately 3 ml. Careful layering of the
concentrated solutions with pentane, followed by cool-
ing to −5°C, afforded colourless to light orange crys-
tals of complexes 1a–1e. Yields were in the range of 45
to 80% without attempting further crystallization from
the mother liquid.
trans-[Pd(OOC–CH2–SEt–k1-O)Ph(PPh3)2]
Light yellow crystals in 75% yield, m.p. 168°C (dec.).
1H-NMR l (d1-chloroform, 298 K): 1.0 (br, 3H,
SCH2CH3), 2.1 (br, 2H, SCH2CH3), 2.6 (br, 2H,
(1b).
3
OOCCH2S), 6.63 (d, 2H, J 7.2 Hz, Pd–C6H5), 6.38 (t,
2H, 3J 6.9 Hz, Pd–C6H5), 6.54 (t, 1H, 3J 7.2 Hz,
Pd–C6H5), 7.2–7.4 (m, 30H, Pd–P(C6H5)3). 13C{1H}-
NMR l (d1-chloroform, 298 K): 14.1 (CH3), 27.4
(SCH2), 36.8 (CH2), 122.2 (Pd–C6H5), 127.2 (Pd–
C6H5), 128.1 (Pd–P(C6H5)3), 129.7 (Pd–P(C6H5)3),
131.2 (Pd–C6H5), 134.3 (Pd–P(C6H5)3), 136.7 (Pd–
P(C6H5)3), 146.4 (Pd–C6H5), 174.7 (Pd–OCO). 31P{1H}
l (d1-chloroform, 298 K): 15–29 (br). IR (KBr): was(CO)
1609 cm−1 (vs). Anal. Calc. for C46H42P2PdO2S: C,
66.8; H, 4.6; S, 3.9. Found: C, 66.6; H, 4.7; S, 3.9%.
trans-[Pd(OOC–CH2–SMe–k1-O)Ph(PPh3)2]
(1a).
Colourless crystals in 80% yield, m.p. 174°C (dec.).
1H-NMR l (d1-chloroform, 298 K): 1.6 (br, 3H, SCH3),
Fig. 5. ORTEP plot of the molecular structure of complex 1h (one of two disordered configurations), showing the numbering scheme.

172
M.W. Esterhuysen et al. / Journal of Organometallic Chemistry 619 (2001) 164–178
Fig. 6. ORTEP plot of the molecular structure of complex 2h, showing the numbering scheme.
trans-[Pd(OOC–CH2–Si-Pr–k1-O)Ph(PPh3)2] (1c).
P(C6H5)3), 145.2 (Pd–C6H5), 177.5 (Pd–OCO). 31P{1H}
l (d1-chloroform, 298 K): 20.5–22.5 (br, S not coordi-
nated), 25–27 (br, S coordinated). IR (KBr): was(CO)
1628 cm−1 (vs). Anal. Calc. for C48H46P2PdO2S: C,
67.4; H, 5.4; S, 3.8. Found: C, 67.7; H, 5.6; S, 3.7%.
Colourless crystals in 45% yield, m.p. 132°C (dec.).
1H-NMR l (d1-chloroform, 298 K): 1.1 (br, 6H,
3
C(CH3)2), 2.7 (br, 3H, SCH and CH2S), 6.71 (d, 2H, J
3
7.2 Hz, Pd–C6H5), 6.44 (t, 2H, J 6.9 Hz, Pd–C6H5),
3
6.56 (t, 1H, J 7.1 Hz, Pd–C6H5), 7.2–7.5 (m, 30H,
trans-[Pd(OOC–CH2–SPh–k1-O)Ph(PPh3)2]
(1e).
Pd–P(C6H5)3). 13C{1H}-NMR l (d1-chloroform, 298
K): 14.1 (CH3), 22.8 (SCH), 35.4 (CH2), 122.4 (Pd–
C6H5), 127.3 (Pd–C6H5), 128.2 (Pd–P(C6H5)3), 129.7
(Pd–P(C6H5)3), 134.3 (Pd–P(C6H5)3), 136.5 (Pd–
P(C6H5)3), 146.2 (Pd–C6H5), 177.3 (Pd–OCO). 31P{1H}
l (d1-chloroform, 298 K): 19.5–23.5 (br, S not coordi-
nated), 23.5–27.0 (br, S coordinated). IR (KBr):
was(CO) 1601 cm−1 (vs). Anal. Calc. for
C47H44P2PdO2S: C, 67.1; H, 5.3; S, 3.8. Found: C, 67.3;
H, 5.3; S, 3.7%.
Colourless crystals in 70% yield, m.p. 127°C (dec.).
1H-NMR l (d1-chloroform, 298 K): 2.7 (br, 2H, CH2S),
3
3
6.97 (d, 2H, J 8.1 Hz, Pd–C6H5), 6.52 (t, 2H, J 9.0
Hz, Pd–C6H5), 6.31 (t, 1H, 3J 7.5 Hz, Pd–C6H5),
6.8–7.8 (m, 35H, Pd–P(C6H5)3 and SC6H5). 13C{1H}-
NMR l (d1-chloroform, 298 K): 38.6 (SCH2), 122.0
(Ph), 124.3 (Ph), 127.1 (Ph), 127.3 (Ph), 128.1 (Ph),
129.8 (Ph), 131.9 (Ph), 132.1 (Ph), 134.5 (Ph), 137.3
(Ph), 146.0 (Ph), 146.4 (Ph), 172.2 (Pd–OCO). 31P{1H}
l (d1-chloroform, 298 K): 21.5 (br). IR (KBr): was(CO)
1615 cm−1 (vs). FAB-MS: m/z 721 [M+−2Ph]. Anal.
Calc. for C50H42P2PdO2S: C, 68.6; H, 4.8; S, 3.7.
Found: C, 68.7; H, 4.9; S, 3.6%.
trans-[Pd(OOC–CH2–St-Bu–k1-O)Ph(PPh3)2] (1d).
Colourless crystals in 45% yield, m.p. 150°C (dec.).
1H-NMR l (d1-chloroform, 298 K): 1.3 (br, 9H,
SC(CH3)3), 3.6 (br, 2H, CH2S), 6.9 (br, 2H, Pd–C6H5),
6.3 (br, 2H, Pd–C6H5), 7.2–7.6 (m, 31H, Pd–P(C6H5)3
and Pd–C6H5). 13C{1H}-NMR l (d1-chloroform, 298
K): 30.3 (SCH2), 35.9 (CH3), 52.0 (SC), 122.7 (Pd–
C6H5), 127.3 (Pd–C6H5), 128.3 (Pd–P(C6H5)3), 130.4
(Pd–P(C6H5)3), 134.4 (Pd–P(C6H5)3), 137.0 (Pd–
3.4. Preparation of
trans-[Pd(OOC–CH2–SMe–s2-O,S)Ph(PPh3)] (2a)
Prolonged crystallization of 1a from THF–pentane
at −5°C afforded small amounts of dark yellow crys-

M.W. Esterhuysen et al. / Journal of Organometallic Chemistry 619 (2001) 164–178
173
Table 1
Crystal data and structure refinement
Identification code
Empirical formula
Formula weight
Temperature (K)
1a
2a
C
586.95
293(2)
C45H40O2P2PdS
813.25
293(2)
27H25O2PPdS·12THF
,
Radiation, wavelength (A)
Crystal system, space group
Unit cell dimensions
Mo–Ka, 0.71073
Monoclinic, P21/n
Mo–Ka, 0.71073
(
Triclinic, P1
,
a (A)
15.9232(7)
15.8426(7)
16.2958(8)
90
109.124(1)
90
9.872(2)
10.266(4)
14.579(3)
85.00(2)
71.561(18)
68.76(2)
1305.7(6)
2, 1.493
,
b (A)
,
c (A)
h (°)
i (°)
k (°)
3
,
Volume (A )
3884.0(3)
4, 1.391
Z, calculated density
(Mg m−3
)
Reflections for cell parameters
Absorption coefficient
19771
0.642
7900
0.828
(mm−1
)
Absorption correction method
Tmin
Empirical (SADABS
0.75
)
Empirical (SADABS)
0.72
Tmax
0.83
0.86
F(000)
1672
600
Crystal size (mm)
Crystal colour
Diffractometer type
Scan type
0.48×0.38×0.30
Colourless
Siemens SMART system
Area detector
0.50×0.33×0.18
Yellow
Siemens SMART system
Area detector
q range for data collection
(°)
1.35–25.00
2.13–27.00
Index ranges
−185h59
−125h56
−185k518
−135k512
−175l519
−185l517
Reflections collected/unique
Refinement method
Data/restraints/parameters
Goodness-of-fit on F2 (S)
Final R indices [I\2|(I)]
R indices (all data)
19771/6770 [Rint=0.0291]
Full-matrix least-squares on F2
6770/0/601
7900/5451 [Rint=0.0151]
Full-matrix least-squares on F2
5451/5/409
1.037
1.047
R1=0.0317, wR2=0.0656
R1=0.0471, wR2=0.0601
calc w=1/[|2(Fo2)+(0.0181P)2+2.5082P] where
P=(F2o+2F2c)/3
R1=0.0291, wR2=0.0711
R1=0.0346, wR2=0.0748
calc w=1/[|2(Fo2)+(0.0336P)2+0.9083P] where
P=(F2o+2F2c)/3
Weighting scheme
Maximum shift/esd
0.001
0.092
Largest difference peak and
0.273 and −0.285
0.379 and −0.470
−3
,
hole (e A
)
Identification code
Empirical formula
Formula weight
Temperature (K)
1h
2h
C
636.85
293(2)
C45H40O2P2PdSe·THF
932.19
296(2)
27H25O2P Pd Se·12C6H6
,
Radiation, wavelength (A)
Crystal system, space group
Unit cell dimensions
Mo–Ka, 0.71073
Monoclinic, P21/n
Mo–Ka, 0.71073
(
Triclinic, P1
,
a (A)
11.9351(6)
24.9638(14)
14.7617(8)
90
97.504(1)
90
9.918(2)
,
b (A)
10.358(2)
14.449(2)
83.756(2)
71.953(2)
67.685(2)
1305.6(4)
2, 1.620
,
c (A)
h (°)
i (°)
k (°)
3
,
Volume (A )
4360.5(4)
4, 1.414
Z, calculated density
(Mg m−3
)

174
M.W. Esterhuysen et al. / Journal of Organometallic Chemistry 619 (2001) 164–178
Table 1 (Continued)
Reflections for cell
parameters
21879
33
Absorption coefficient
1.374
2.192
(mm−1
)
Absorption correction
method
Empirical (SADABS
)
Empirical (ABSCAL)
Tmin
0.64
0.48
Tmax
0.80
0.65
F(000)
1888
638
Crystal size (mm)
Crystal colour
Diffractometer type
Scan type
0.42×0.28×0.16
Colourless
Siemens SMART system
Area detector
0.35×0.28×0.20
Orange
Philips PW1100
ꢀ–2q
q range for data collection
(°)
1.61–25.00
2.97–25.85
Index ranges
−145h513
−235k529
−165l517
−115h511
−105k512
−175l51
Reflections collected/unique
Refinement method
Data/restraints/parameters
Goodness-of-fit on F2 (S)
Final R indices [I\2|(I)]
R indices (all data)
21879/7591 [Rint=0.0430]
Full-matrix least-squares on F2
7591/9/477
5713/4866 [Rint=0.0154]
Full-matrix least-squares on F2
4866/0/304
1.062
1.106
R1=0.0634, wR2=0.1540
R1=0.0832, wR2=0.1650
calc w=1/[|2(Fo2)+(0.0818P)2+11.7107P] where
P=(F2o+2F2c)/3
R1=0.0376, wR2=0.0968
R1=0.0533, wR2=0.1121
calc w=1/[|2(Fo2)+(0.0411P)2+2.2539P] where
P=(F2o+2F2c)/3
Weighting scheme
Maximum shift/esd
0.059
0.044
Largest difference peak and
1.675 and −1.043 close to Se
0.896 and −0.903 close to Pd
−3
,
hole (e A
)
tals of 2a amongst colourless crystals of 1a that were
manually separated under a microscope in a less than
5% yield.
Table 2
Selected bond lengths (A)
,
trans-[Pd(OOC–CH2–SMe–k2-O,S)Ph(PPh3)] (2a).
Dark yellow crystals in B5% yield, m.p. 132°C (dec.).
1H-NMR l (d1-chloroform, 298 K): 2.37 (s, 3H, SCH3),
3.62 (s, 2H, CH2S), 6.5–7.0 (m, 5H, Pd–C6H5), 6.8–7.3
(m, 15H, Pd–P(C6H5)3). 13C{1H}-NMR l (d1-chloro-
form, 298 K): 20.4 (SCH3), 40.5 (SCH2), 123.1 (Pd–
C6H5), 127.8 (Pd–C6H5), 128.4 (Pd–P(C6H5)3), 129.4
(Pd–P(C6H5)3), 130.6 (Pd–C6H5), 134.2 (Pd–
P(C6H5)3), 138.0 (Pd–P(C6H5)3), 145.8 (Pd–C6H5).
31P{1H} l (d1-chloroform, 298 K): 27.3 (s). IR (KBr):
was(CO) 1631 cm−1 (s). FAB-MS: m/z 551 [M+]. Anal.
Calc. for C27H25PPdO2S: C, 58.9; H, 4.6; S, 5.8. Found:
C, 59.1; H, 4.7; S, 5.5%.
1a
Pd–C(4)
Pd–O(1)
Pd–P(1)
2a
1.998(3)
2.112(2)
2.3367(7)
2.3530(7)
1.264(4)
1.217(4)
1.527(6)
1.674(15)
1.792(7)
1.672(15)
1.707(15)
1.63(3)
Pd–C(4)
Pd–O(1)
Pd–P
2.007(3)
2.1095(19)
2.2827(8)
2.3430(9)
1.273(3)
1.227(3)
1.524(4)
1.813(3)
1.799(4)
Pd–P(2)
Pd–S
O(1)–C(1)
O(2)–C(1)
C(1)–C(2a)
C(1)–C(2b)
S(a)–C(2a)
S(a)–C(3a)
S(b)–C(2b)
S(b)–C(3b)
O(1)–C(1)
C(1)–O(2)
C(1)–C(2)
S–C(2)
S–C(3)
1h
2h
Pd–C(4)
Pd–O(1)
Pd–P(1)
2.011(6)
2.104(4)
2.3369(14)
2.3336(14)
1.262(8)
Pd–C(4)
Pd–O(1)
Pd–P
2.007(4)
2.101(3)
2.2856(10)
2.4307(5)
1.274(5)
1.224(5)
1.524(6)
1.944(5)
1.939(6)
3.5. Preparation of
trans-[Pd(OOC–{CH2}2–SR–s1-O)Ph(PPh3)2] (1f
R=Et; 1g R=Ph)
Pd–P(2)
Pd–Se
O(1)–C(1)
O(2)–C(1)
C(1)–C(2)
Se(a)–C(2)
Se(a)–C(3)
Se(b)–C(2)
Se(b)–C(3)
O(1)–C(1)
O(2)–C(1)
C(1)–C(2)
Se–C(2)
Se–C(3)
1.222(8)
1.503(13)
1.812(11)
1.881(11)
1.672(13)
1.878(13)
Complexes 1f and 1g were obtained in the same
manner as complexes 1a–1e, described in Section 3.3,
with RS–(CH2)2–COOH (0.48 mmol, R=Et, Ph) as
ligands. Careful layering of the concentrated solutions
in THF with pentane, followed by cooling to −5°C,

M.W. Esterhuysen et al. / Journal of Organometallic Chemistry 619 (2001) 164–178
175
Table 3
Selected bond angles (°)
Calc. for C47H44P2PdO2S: C, 67.1; H, 5.3; S, 3.9.
Found: C, 66.9; H, 5.3; S, 3.9%.
trans-[Pd(OOC–(CH2)2–SPh–k1-O)Ph(PPh3)2] (1g).
Light violet crystals in 32% yield, m.p. 139°C (dec.).
1H-NMR l (d1-chloroform, 298 K): 1.4 (br, 2H, CH2S,
S not coordinated), 2.4 (br, 2H, CH2S, S coordinated),
2.2 (br, 2H, OOCCH2, S not coordinated), 3.2 (br, 2H,
OOCCH2, S coordinated), 6.57 (d, 2H, 3J 7.2 Hz,
1a
2a
C(4)–Pd–O(1)
C(4)–Pd–P(1)
O(1)–Pd–P(1)
C(4)–Pd–P(2)
O(1)–Pd–P(2)
P(1)–Pd–P(2)
C(1)–O(1)–Pd
O(2)–C(1)–O(1)
O(2)–C(1)–C(2a)
O(1)–C(1)–C(2a)
O(2)–C(1)–C(2b) 126.4(5)
O(1)–C(1)–C(2b) 102.8(6)
C(1)–C(2a)–S(a)
C(1)–C(2b)–S(b)
C(2a)–S(a)–C(3a) 100.4(5)
C(2b)–S(b)–C(3b) 109.3(11)
179.58(9)
C(4)–Pd–O(1)
C(4)–Pd–P
O(1)–Pd–P
C(4)–Pd–S
O(1)–Pd–S
P–Pd–S
C(1)–O(1)–Pd
C(2)–S–C(3)
C(2)–S–Pd
C(3)–S–Pd
170.92(8)
93.16(7)
95.56(6)
87.59(7)
83.93(6)
175.29(2)
121.71(17)
101.9(2)
97.85(10)
107.88(14)
87.71(8)
91.87(5)
85.01(8)
95.40(5)
172.71(3)
117.3(2)
126.2(3)
115.4(4)
117.8(3)
3
Pd–C6H5), 6.30 (t, 2H, J 7.2 Hz, Pd–C6H5), 6.51 (t,
1H, 3J 7.2 Hz, Pd–C6H5), 7.0–7.8 (m, 35H, Pd–
P(C6H5)3 and SC6H5). 13C{1H}-NMR l (d1-chloroform,
298 K): 29.1 (CH2S), 36.8 (CH2CH2S), 121.8 (Pd–
C6H5), 125.0 (S–Ph), 127.0 (Pd–C6H5), 127.9 (Pd–
P(C6H5)3), 128.4 (S–Ph), 129.7 (Pd–P(C6H5)3), 130.3
(Pd–C6H5), 130.8 (S–Ph), 134.4 (Pd–P(C6H5)3), 135.9
(S–Ph), 137.3, 137.5 (Pd–P(C6H5)3), 146.7 (Pd–C6H5),
175.1 (Pd–OCO). 31P{1H} l (d1-chloroform, 298 K):
21.8 (s, S not coordinated), 23.9 (s, S coordinated). IR
(KBr): was(CO) 1604 cm−1 (vs). FAB-MS: m/z 736
[M+−2Ph]. Anal. Calc. for C51H44P2PdO2S: C, 68.9;
H, 5.0; S, 3.6. Found: C, 68.7; H, 5.2; S, 3.7%.
O(2)–C(1)–O(1) 124.7(3)
O(2)–C(1)–C(2) 116.5(2)
O(1)–C(1)–C(2) 118.7(2)
109.7(4)
114.4(10)
C(1)–C(2)–S
115.3(2)
1h
2h
C(4)–Pd–O(1)
C(4)–Pd–P(1)
O(1)–Pd–P(1)
C(4)–Pd–P(2)
O(1)–Pd–P(2)
P(1)–Pd–P(2)
C(1)–O(1)–Pd
O(2)–C(1)–O(1)
O(2)–C(1)–C(2)
O(1)–C(1)–C(2)
C(1)–C(2)–Se(a)
C(1)–C(2)–Se(b)
C(2)–Se(a)–C(3)
C(2)–Se(b)–C(3)
177.0(2)
88.79(16)
91.85(12)
87.22(16)
92.42(12)
173.34(5)
116.9(4)
126.4(7)
121.8(8)
111.8(7)
131.2(9)
119.9(8)
102.9(6)
108.8(6)
C(4)–Pd–O(1)
C(4)–Pd–P
O(1)–Pd–P
C(4)–Pd–Se
O(1)–Pd–Se
P–Pd–Se
C(1)–O(1)–Pd
C(2)–Se–C(3)
C(2)–Se–Pd
C(3)–Se–Pd
169.99(13)
93.59(11)
95.40(8)
86.61(11)
84.90(8)
174.19(3)
124.1(3)
99.0(3)
3.6. Preparation of
trans-[Pd(OOC–CH2–SeR–s1-O)Ph(PPh3)2] (1h
R=Me; 1i R=Ph)
94.30(14)
103.9(2)
Complexes 1h and 1i were obtained in the same
manner as complexes 1a–1e, described in Section 3.3,
with RSe–CH2–COOH (0.48 mmol, R=Me, Ph) as
ligands. Careful layering of the concentrated solutions
in THF with pentane, followed by cooling to −5°C,
afforded colourless crystals of complexes 1h and 1i.
Yields were high without attempting further crystalliza-
tion from the mother liquid.
O(2)–C(1)–O(1) 124.6(4)
O(2)–C(1)–C(2) 116.2(4)
O(1)–C(1)–C(2) 119.1(4)
C(1)–C(2)–Se
115.3(3)
afforded light yellow and light violet crystals of com-
plexes 1f and 1g respectively. Yields were moderate to
low without attempting further crystallization from the
mother liquid.
trans-[Pd(OOC–CH2–SeMe–k1-O)Ph(PPh3)2] (1h).
Colourless crystals in 80% yield, m.p. 156.5–157.5°C.
1H-NMR l (d1-chloroform, 298 K): 1.8 (br, 3H,
trans-[Pd(OOC–(CH2)2–SEt–k1-O)Ph(PPh3)2] (1f).
Light yellow crystals in 45% yield, m.p. 175°C (dec.).
1H-NMR l (d1-chloroform, 298 K): 1.2 (br, 3H, CH3, S
not coordinated), 1.1 (br 3H, CH3, S coordinated), 2.4
(br, 2H, SCH2CH3, S not coordinated), 2.2 (br, 2H,
SCH2CH3, S coordinated), 2.8 (br, 2H, CH2S, S not
coordinated), 1.2 (br, 2H, CH2S, S coordinated), 3.2
(br, 2H, OOCCH2, S not coordinated), 2.3 (br, 2H,
OOCCH2, S coordinated), 6.55 (d, 2H, 3J 7.2 Hz,
3
SeCH3), 2.8 (br, 2H, CH2Se), 6.64 (d, 2H, J 7.5 Hz,
3
Pd–C6H5), 6.38 (t, 2H, J 7.5 Hz, Pd–C6H5), 6.54 (t,
1H, 3J 7.2 Hz, Pd–C6H5), 7.2–7.9 (m, 30H, Pd–
P(C6H5)3). 13C{1H}-NMR l (d1-chloroform, 298 K):
31.1 (CH2Se), 122.2 (Pd–C6H5), 127.3 (Pd–C6H5),
128.2 (Pd–P(C6H5)3), 129.8 (Pd–P(C6H5)3), 131.4 (Pd–
C6H5), 134.4 (Pd–P(C6H5)3), 136.7 (Pd–P(C6H5)3),
146.2 (Pd–C6H5), 175.8 (Pd–OCO). 31P{1H} l (d1-chlo-
roform, 298 K): 16–27 (br). 77Se{1H} l (d1-chloroform,
223 K): 83.9. IR (KBr): was(CO) 1600 cm−1 (vs). Anal.
Calc. for C45H40P2PdO2Se: C, 62.8; H, 4.7. Found: C,
63.0; H, 4.8%.
3
Pd–C6H5), 6.28 (t, 2H, J 7.5 Hz, Pd–C6H5), 6.49 (t,
1H, 3J 7.2 Hz, Pd–C6H5), 7.2–7.5 (m, 30H, Pd–
P(C6H5)3). 13C{1H}-NMR l (d1-chloroform, 298 K):
14.7 (br, CH3), 25.2 (SCH2CH3), 25.5 (SCH2CH3), 27.4
(CH2S), 27.8 (CH2S), 37.5 (CH2CH2S), 40.0
(CH2CH2S), 121.8 (Pd–C6H5), 127.0 (Pd–C6H5), 127.9
(Pd–P(C6H5)3), 129.7 (Pd–P(C6H5)3), 130.3 (Pd–
C6H5), 134.5 (Pd–P(C6H5)3), 137.6 (Pd–P(C6H5)3),
146.7 (Pd–C6H5), 175.7 (Pd–OCO). 31P{1H} l (d1-chlo-
roform, 298 K): 21.7 (s, S not coordinated), 23.9 (s, S
coordinated). IR (KBr): was(CO) 1617 cm−1 (vs). Anal.
trans-[Pd(OOC–CH2–SePh–k1-O)Ph(PPh3)2]
(1i).
Colourless crystals in 75% yield, m.p. 154.5–155.5°C.
1H-NMR l (d1-chloroform, 298 K): 2.7 (br, 2H,
3
CH2Se), 6.56 (d, 2H, J 7.8 Hz, Pd–C6H5), 6.31 (t, 2H,
3J 7.5 Hz, Pd–C6H5), 6.51 (t, 1H, 3J 7.8 Hz, Pd–C6H5),
7.0–7.6 (m, 35H, Pd–P(C6H5)3 and Se(C6H5)).
13C{1H}-NMR l (d1-chloroform, 298 K): 35.0 (CH2Se),

176
M.W. Esterhuysen et al. / Journal of Organometallic Chemistry 619 (2001) 164–178
125.4 (Pd–C6H5), 128.2 (Se–Ph), 128.4 (Se–Ph), 128.7
(Pd–P(C6H5)3), 130.8 (Pd–P(C6H5)3), 131.0 (Se–Ph),
132.1 (Pd–C6H5), 133.4 (Se–Ph), 134.4 (Pd–P(C6H5)3),
135.9 (Pd–P(C6H5)3), 174.1 (Pd–OCO). 31P{1H} l (d1-
chloroform, 298 K): 18–28 (br). 77Se{1H} l (d1-chloro-
form, 223 K): 268.1. IR (KBr): was(CO) 1611 cm−1 (vs).
FAB-MS: m/z 922 [M+]. Anal. Calc. for C50H42-
P2PdO2Se: C, 65.1; H, 4.6. Found: C, 65.0; H, 4.5%.
Table 4
4
3
,
Atomic coordinates (×10 ) and equivalent isotropic displacement parameters (A ×10 ) of complex 1a, Ueq is defined as one third of the trace
of the orthogonalized Uij tensor
Atom
x
y
z
Ueq
Atom
x
y
z
Ueq
Pd
P(1)
P(2)
O(1)
O(2)
S(a)
S(b)
2809(1)
1434(1)
4129(1)
3201(1)
2543(2)
2777(2)
2879(3)
503(2)
179
431(1)
8050
34(1)
C(213)
C(214)
C(215)
C(216)
C(221)
C(222)
C(223)
C(224)
C(225)
C(226)
C(231)
C(232)
C(233)
C(234)
C(235)
C(236)
C(1)
C(2a)
C(2b)
C(3a)
C(3b)
C(4)
C(5)
C(6)
C(7)
C(8)
5943(3)
6679(3)
6648(3)
5876(2)
3953(2)
3360(2)
3235(2)
3687(3)
4272(3)
4406(3)
4587(2)
4294(2)
4658(3)
5298(2)
5574(2)
5223(2)
3004(2)
3477(3)
3136(10)
1950(6)
1810(20)
2430(2)
2000(2)
1732(3)
1884(3)
2310(3)
2582(2)
1507(3)
1327(3)
695(3)
238(2)
−323(2)
233(2)
9186(3)
8972(3)
8391(3)
8013(3)
6655(2)
6109(2)
5229(2)
4884(2)
5409(3)
6293(2)
8282(2)
7871(2)
8247(3)
9056(3)
9486(2)
9103(2)
7698(3)
7838(4)
8192(10)
7118(10)
6992(14)
7786(2)
6937(2)
6739(4)
7387(4)
8229(4)
8433(3)
78(1)
8230(1)
7819(1)
8330(1)
6954(2)
8068(2)
7501(6)
7220(2)
6466(2)
5709(2)
5692(2)
6431(2)
7195(2)
8859(2)
9707(2)
10155(3)
9764(3)
8932(3)
8479(2)
8775(2)
8456(2)
8901(3)
9675(3)
10001(2)
9550(2)
8234(2)
8821(2)
37(1)
40(1)
48(1)
78(1)
106(1)
105(3)
38(1)
51(1)
66(1)
65(1)
65(1)
54(1)
44(1)
59(1)
80(1)
81(2)
78(1)
63(1)
42(1)
50(1)
65(1)
70(1)
69(1)
58(1)
47(1)
60(1)
83(1)
88(2)
68(1)
46(1)
47(1)
60(1)
75(1)
97(2)
81(1)
42(1)
60(1)
73(1)
67(1)
61(1)
51(1)
59(1)
58(1)
74(4)
217(11)
106(9)
42(1)
56(1)
83(1)
95(2)
88(2)
61(1)
−250(1)
1449(1)
1813(1)
3602(2)
3745(2)
504(2)
759(2)
858(2)
696(3)
443(2)
243(2)
C(111)
C(112)
C(113)
C(114)
C(115)
C(116)
C(121)
C(122)
C(123)
C(124)
C(125)
C(126)
C(131)
C(132)
C(133)
C(134)
C(135)
C(136)
C(211)
C(212)
−307(3)
−866(3)
−873(3)
−1266(2)
−2027(2)
−2779(2)
−2782(2)
−2042(2)
−1292(2)
1963(2)
2815(3)
2903(8)
3632(9)
3752(16)
−1021(2)
−1272(2)
−2104(3)
−2690(3)
−2458(3)
−1628(2)
644(2)
−64(2)
−914(3)
−1067(2)
−364(2)
1047(2)
1090(2)
788(3)
452(3)
417(3)
711(2)
1408(2)
752(2)
349(2)
−346(2)
−216(3)
−829(3)
−1565(3)
−1718(3)
−1113(2)
1430(2)
2036(2)
2783(2)
2929(2)
2340(3)
1602(3)
411(2)
774(3)
1436(3)
2089(3)
2086(2)
5121(2)
5163(2)
1046(2)
C(9)
Table 5
4
3
,
Atomic coordinates (×10 ) and equivalent isotropic displacement parameters (A ×10 ) of complex 2a, Ueq is defined as one third of the trace
of the orthogonalized Uij tensor
Atom
x
y
z
Ueq
Atom
x
y
z
Ueq
Pd
P
O(1)
O(2)
6616(1)
2739(1)
3428(1)
3781(2)
4264(3)
1883(1)
4469(2)
4411(3)
5357(3)
6354(3)
6407(3)
5462(3)
4592(3)
4136(3)
4959(4)
6236(4)
6705(3)
5889(3)
2063(3)
2396(3)
3520(1)
2153(1)
4494(1)
6009(2)
4929(1)
1348(2)
344(2)
31(1)
30(1)
48(1)
74(1)
42(2)
33(1)
40(1)
48(1)
53(1)
49(1)
40(1)
34(1)
47(1)
61(1)
64(1)
59(1)
43(1)
35(1)
44(1)
C(133)
C(134)
C(135)
C(136)
C(1)
C(2)
C(3)
C(4)
C(5)
C(6)
C(7)
C(8)
C(9)
O(52)
C(51)
C(53)
C(54)
C(55)
12162(3)
12218(4)
11090(5)
9838(4)
6542(3)
5383(4)
3312(4)
5881(3)
4674(3)
3966(4)
4456(4)
5651(4)
6351(3)
9570(2)
8971(17)
10384(17)
10560(2)
9320(2)
1373(3)
22(4)
−330(4)
687(3)
3724(3)
2996(4)
2559(6)
1730(3)
2445(3)
1737(4)
296(4)
131(2)
163(3)
811(4)
51(1)
8070(1)
7098(2)
6822(3)
5308(1)
7032(3)
7648(3)
6857(4)
5461(4)
4821(4)
5593(3)
8950(3)
9835(3)
10577(4)
10428(4)
9546(4)
8802(3)
9734(3)
10931(3)
64(1)
97(2)
71(1)
45(1)
55(1)
69(1)
36(1)
43(1)
53(1)
55(1)
51(1)
42(1)
263(9)
126(4)
125(4)
214(10)
171(7)
1430(3)
5407(2)
5798(2)
5023(3)
2773(2)
2410(2)
2060(2)
2050(2)
2404(2)
2769(2)
5850(12)
5515(11)
5063(13)
4099(13)
4438(11)
S
C(111)
C(112)
C(113)
C(114)
C(115)
C(116)
C(121)
C(122)
C(123)
C(124)
C(125)
C(126)
C(131)
C(132)
−213(2)
221(2)
1216(2)
1777(2)
2423(2)
3047(2)
3238(3)
2824(3)
2220(3)
2011(2)
1384(2)
735(2)
−438(3)
265(3)
10370(2)
9612(17)
10842(14)
10230(3)
9660(2)

M.W. Esterhuysen et al. / Journal of Organometallic Chemistry 619 (2001) 164–178
177
Table 6
4
3
,
Atomic coordinates (×10 ) and equivalent isotropic displacement parameters (A ×10 ) of complex 1h, Ueq is defined as one third of the trace
of the orthogonalized Uij tensor
Atom
x
y
z
Ueq
Atom
x
y
z
Ueq
Pd
P(1)
P(2)
O(1)
O(2)
Se(a)
Se(b)
3836(1)
9019(1)
9206(1)
8802(1)
9774(2)
2526(1)
2818(1)
2414(1)
1919(3)
3275(3)
2320(1)
2177(5)
4032(4)
4380(4)
5298(5)
5860(5)
5519(5)
4606(4)
2302(4)
2821(5)
2392(5)
1470(6)
956(5)
1378(4)
2454(4)
1736(5)
1473(6)
1925(6)
2637(6)
2907(5)
3542(4)
4240(4)
5100(5)
5277(5)
36(1)
C(215)
C(216)
C(221)
C(222)
C(223)
C(224)
C(225)
C(226)
C(231)
C(232)
C(233)
C(234)
C(235)
C(236)
C(1)
C(2)
C(3)
C(4)
C(5)
C(6)
C(7)
C(8)
C(9)
8109(7)
7500(5)
5978(5)
5910(6)
6044(8)
6246(7)
6301(7)
6161(5)
6468(5)
7497(5)
8046(6)
7579(6)
6572(6)
6003(5)
4336(6)
4503(11)
5116(10)
3680(5)
3905(5)
3777(7)
3416(7)
3193(7)
3317(6)
8035(15)
6856(14)
6910(2)
8010(2)
8140(4)
8443(4)
8445(3)
8180(3)
7693(3)
7216(3)
7224(4)
7695(4)
8180(3)
9308(2)
9515(3)
9902(3)
10084(3)
9882(3)
9504(3)
10154(3)
10658(5)
11445(5)
8281(2)
8175(3)
7660(3)
7254(3)
7347(3)
7861(3)
1401(7)
1446(8)
1989(10)
2105(11)
1625(12)
4591(6)
3711(5)
1820(4)
2243(6)
1779(8)
897(9)
459(6)
896(5)
1840(4)
2234(4)
1773(5)
928(5)
79(2)
1998(1)
5714(1)
3983(3)
4546(6)
4033(1)
5348(6)
1900(5)
871(6)
36(1)
38(1)
50(1)
84(2)
90(1)
183(3)
40(1)
56(2)
78(2)
81(2)
71(2)
51(2)
42(1)
50(2)
65(2)
70(2)
70(2)
58(2)
41(1)
57(2)
72(2)
71(2)
69(2)
54(2)
43(1)
54(2)
72(2)
80(2)
60(2)
50(2)
68(2)
92(3)
101(3)
86(3)
64(2)
42(1)
50(2)
59(2)
64(2)
66(2)
55(2)
62(2)
128(4)
128(4)
44(1)
55(2)
78(2)
85(3)
82(3)
62(2)
259(7)
203(7)
338(15)
298(13)
500(3)
10135(2)
11295(1)
11186(2)
9294(2)
9219(3)
9310(3)
9467(3)
9554(3)
9465(3)
9838(2)
10251(2)
10720(3)
10780(3)
10380(3)
9914(3)
8721(2)
8810(3)
8426(3)
7952(3)
7854(3)
8233(3)
8750(2)
9058(3)
9050(3)
8730(4)
C(111)
C(112)
C(113)
C(114)
C(115)
C(116)
C(121)
C(122)
C(123)
C(124)
C(125)
C(126)
C(131)
C(132)
C(133)
C(134)
C(135)
C(136)
C(211)
C(212)
C(213)
C(214)
831(7)
1767(8)
2762(7)
2833(5)
1466(4)
1089(5)
685(6)
534(5)
982(4)
2442(5)
1919(8)
3332(8)
3041(4)
3964(5)
4300(6)
3724(8)
2813(7)
2470(5)
9908(13)
9964(13)
649(6)
1036(6)
1462(6)
877(4)
34(5)
−786(6)
−755(6)
56(6)
O(51)
C(51)
C(52)
C(53)
C(54)
874(5)
6532(5)
6198(5)
6817(7)
7744(8)
10440(2)
10139(19)
10790(15)
Table 7
4
3
,
Atomic coordinates (×10 ) and equivalent isotropic displacement parameters (A ×10 ) of complex 2h, Ueq is defined as one third of the trace
of the orthogonalized Uij tensor
Atom
x
y
z
Ueq
Atom
x
y
z
Ueq
Pd
P
O(1)
O(2)
3326(1)
2288(1)
1565(1)
1192(3)
672(4)
3262(1)
418(4)
1455(1)
2834(1)
486(2)
−1009(2)
−7(1)
36(1)
35(1)
50(1)
64(1)
44(1)
38(1)
47(1)
60(1)
66(2)
65(1)
51(1)
37(1)
45(1)
55(1)
59(1)
52(1)
44(1)
41(1)
C(132)
C(133)
C(134)
C(135)
C(136)
C(1)
C(2)
C(3)
C(4)
C(5)
C(6)
C(7)
C(8)
C(9)
C(51)
C(52)
C(56)
−948(5)
2600(5)
3612(6)
4923(7)
5257(7)
4262(6)
1240(5)
2010(6)
2407(7)
3306(4)
4761(5)
5454(5)
4723(6)
3294(6)
2588(5)
5552(10)
6059(13)
4535(12)
4215(4)
4820(4)
4814(5)
4195(7)
3578(6)
−437(3)
−886(3)
−75(4)
2196(3)
2216(3)
2590(3)
2920(3)
2891(3)
2535(3)
9327(7)
10239(8)
9059(9)
53(1)
1918(1)
2935(4)
3141(4)
4590(1)
1050(5)
1134(5)
400(6)
−455(6)
−565(6)
192(5)
2984(5)
4438(5)
5214(6)
4585(6)
3171(6)
2372(5)
257(5)
−2183(5)
−2214(7)
−1089(10)
154(8)
57(1)
84(2)
146(5)
108(3)
46(1)
57(1)
68(1)
40(1)
48(1)
54(1)
58(1)
58(1)
48(1)
119(3)
139(4)
134(3)
Se
C(111)
C(112)
C(113)
C(114)
C(115)
C(116)
C(121)
C(122)
C(123)
C(124)
C(125)
C(126)
C(131)
2577(3)
3042(3)
2853(4)
2215(4)
1749(5)
1923(3)
3656(3)
3236(3)
3801(4)
4801(4)
5224(3)
4656(3)
3602(3)
3435(5)
4520(7)
6730(6)
4036(5)
3510(6)
4183(6)
5420(6)
5963(6)
5279(5)
936(11)
246(12)
636(13)
−843(5)
−1633(5)
−1166(6)
74(7)
868(5)
510(4)
−449(5)
−1392(5)
−1372(6)
−393(5)
542(5)
2906(5)

178
M.W. Esterhuysen et al. / Journal of Organometallic Chemistry 619 (2001) 164–178
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3.7. Preparation of trans-[Pd(OOC–CH2–
SeMe–s2-O,Se)Ph(PPh3)] (2h)
Prolonged crystallization of 1h from benzene–pen-
tane at 5°C afforded small amounts of dark yellow
crystals of 2h amongst colourless crystals of 1h that
were manually separated under a microscope in a less
than 5% yield.
trans - [Pd(OOC – CH2 – SeMe – k2 - O,Se)Ph(PPh3)]
(2h). Dark yellow crystals in B5% yield, m.p. 165.5–
166.5°C. IR (KBr): was(CO) 1621 cm−1 (s). Anal. Calc.
for C27H25PPdO2Se: C, 54.2; H, 4.2. Found: C, 54.0; H,
3.8%.
[16] L. Malatesta, M. Angoletta, J. Chem. Soc. (1957) 1186.
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Bull. Chem. Soc. Jpn. 57 (1984) 395.
4. Supplementary material
Crystallographic data for the structures reported in
this paper have been deposited with the Cambridge
Crystallographic Data Centre, CCDC nos. 132643–
132646. Copies of this information may be obtained
free of charge from the Director, CCDC, 12 Union
Road, Cambridge, CB2 1EZ, UK (fax: +44-1223-336-
033; e-mail: deposit@ccdc.cam.ac.uk or http://
www.ccdc.cam.ac.uk).
8
[20] W.A. Herrmann, C. Brobner, T. Priermeier, K. Ofele, J.
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Chem. 460 (1993) 31.
Acknowledgements
[28] L.A. Silks III, J.D. Odom, R.B. Dunlap, Synth. Commun. 21
(1991) 1105.
We thank the FRD for financial support. The mea-
surement of NMR spectra by Dr L. van der Merwe and
Mr I. Vorster is gratefully acknowledged.
[29] G.M. Sheldrick, SADABS, Program for Empirical Absorption
Correction of Area-Detector Data, University of Go¨ttingen,
Germany, 1996.
[30] M. Gomm, PWPC v 1.12/H, Control Program for PW1100
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