Synthesis and structural studies of molybdenum and palladium complexes of 1,5-diaza-3,7-diphosphacyclooctane ligands

Article abstract of DOI:10.1016/S0277-5387(98)00413-6

1,5-Diaza-3,7-diphosphacyclooctanes form 1:1 complexes with the metal fragments Mo(CO)₄ and PdCl₂. Two of these products along with a parent heterocycle have been structurally characterized. The [P(Ph)CH₂N(2-pyridyl)CH₂]₂ ring is found in a crown conformation while its cis-Mo(CO)₄ complex adopts a chair-boat ligand conformation. On the other hand, the cis-PdCl₂ complex of [P(Ph)CH₂N(Bz)CH₂]₂ is found to retain a highly flattened crown ligand conformation. Unlike the related eight-membered heterocycle 1,3,5,7-tetraoxa-2,4,6,8-tetraphosphacyclooctane which behaves as a tetradentate ligand chelating homo- or hetero-bimetallics, coordination to a second metal by these complexes was not realized.

Full text of DOI:10.1016/S0277-5387(98)00413-6

Polyhedron 18 (1999) 1183–1188
Synthesis and structural studies of molybdenum and palladium complexes
of 1,5-diaza-3,7-diphosphacyclooctane ligands
b
b
John C. Kanea, Edward H. Wonga, , Glenn P.A. Yap , Arnold L. Rheingold
*
aDepartment of Chemistry, University of New Hampshire, Durham, NH 03824, USA
bDepartment of Chemistry, University of Delaware, Newark, DE 19716, USA
Received 1 July 1998; accepted 23 October 1998
Abstract
1,5-Diaza-3,7-diphosphacyclooctanes form 1:1 complexes with the metal fragments Mo(CO)4 and PdCl2. Two of these products along
with a parent heterocycle have been structurally characterized. The [P(Ph)CH2N(2-pyridyl)CH2]2 ring is found in a crown conformation
while its cis-Mo(CO)4 complex adopts a chair–boat ligand conformation. On the other hand, the cis-PdCl2 complex of
[P(Ph)CH2N(Bz)CH2]2 is found to retain a highly flattened crown ligand conformation. Unlike the related eight-membered heterocycle
1,3,5,7-tetraoxa-2,4,6,8-tetraphosphacyclooctane which behaves as a tetradentate ligand chelating homo- or hetero-bimetallics, coordina-
tion to a second metal by these complexes was not realized.
1999 Elsevier Science Ltd. All rights reserved.
Keywords: Molybdenum; Palladium; Phosphorus; Heterocycles; Metal complexes
1. Introduction
adopt one of eight coordination modes [10], led us to
reexamine the potentially tetradentate 1,5-diaza-3,7-
diphosphacyclooctanes which were first prepared by Markl
et al. in 1980 [11]. Monometallic metal complexes featur-
ing 1:1 and 1:2 metal/ligand ratios have been synthesized
and structural studies of two Pt(II) and one Cu(I) as well
as a single parent heterocycle, [P(Ph)CH2N(Ph)CH2]2,
have appeared [12–15]. We report herein the structure of
the [P(Ph)CH2N(2-pyridyl)CH2]2 heterocycle (ligand 1)
and syntheses and structures of its Mo(CO)4 complex as
well as the PdCl2 complex of [P(Ph)CH2N(Bz)CH2]2
(ligand 2).
Eight-membered rings containing two or more donor
atoms have a coordination chemistry between multidentate
macrocycles and smaller heterocycles that have limited
chelating ability [1–4]. If these donor atoms are in the 1,5
positions, chelation of a metal can potentially result in one
of several possible ligand conformations including chair–
chair, boat–boat and chair–boat (Fig. 1). The most
common of these found in solid-state structures appears to
be the chair–boat, although the boat–boat form has been
observed in a number of six-coordinate complexes [1–9].
Our interest in tetraphosphorus heterocyclic ligands, espe-
cially the 1,3,5,7-tetraoxa-2,4,6,8-tetraphosphacyclooctane
rings (or cyclotetraphosphoxane [RP–O]4) which can
2. Experimental
2.1. General considerations
The ligands [P(Ph)CH2N(2-pyridyl)CH2]2, 1, and
[P(Ph)CH2N(Bz)CH2]2, 2, were prepared according to the
literature method [11]. Mo(CO)4(h2-norbornadiene),
PdCl2 –2PhCN, and NiCl2 –(dimethoxyethane) were ob-
tained using the literature procedures [16–18]. All com-
plexes were prepared and handled under a nitrogen atmos-
phere using standard Schlenk techniques. Solvents were
reagent grade and dried and distilled under nitrogen
immediately before use. Elemental analyses were per-
Fig. 1. Eight-membered ligand ring chelating conformations.
*
Corresponding author.
0277-5387/99/$ – see front matter
PII: S0277-5387(98)00413-6
1999 Elsevier Science Ltd. All rights reserved.

1184
J.C. Kane et al. / Polyhedron 18 (1999) 1183–1188
formed on a Perkin-Elmer 2400 Elemental Analyzer.
Proton, 13C, and 31P NMR spectra were recorded on
JEOL-FX-90Q spectrometer and a Bruker AM 360 spec-
trometer. IR spectra of products were obtained as KBr
pellets using a Nicolet MX-1 FT-spectrophotometer.
residue washed with cold toluene to give 0.13 g (49%) of
the product NiCl2 –2. Small, branched purple crystals were
obtained from CH2Cl2 /hexane. Analysis from calculation
for C30H32Cl2N2NiP2: C, 58.86%; H, 5.27%; N, 4.58%
Found: C, 59.05%; H, 5.62%; N, 4.53%.
2.3. Attempts at synthesis of bimetallic complexes
2.2. Syntheses
Use of excess metal reagents (Mo(CO)4 –nbd, PdCl2 –
2PhCN or NiCl2 –dme) in the above preparations failed to
yield any isolable bimetallic products. Further attempts at
coordination of a second metal (NiCl2, CoCl2, ZnCl2, etc.)
at the open nitrogen donor sites in the monometallic
complexes Mo(CO)4 –1, PdCl2 –2 and NiCl2 –2 were also
unsuccessful.
2.2.1. Mo(CO)4 [P(Ph)CH2N(2-pyridyl)CH2 ]2 , Mo(CO)4 –
1
To a flask containing 0.37 g (0.86 mmol) of ligand 1
and 0.30 g (0.99 mmol) of Mo(CO)4(h2-norbornadiene)
was added 30 ml of methylene chloride. After stirring at
room temperature for 20 h, the yellow solution was
concentrated to 15 ml and 20 ml of hexane was added to
precipitate a small amount of brown material. This was
filtered off and to the filtrate was added a further 25 ml
hexane. The yellow precipitate formed was filtered off,
washed with hexane, and dried to give 0.35 (64%) of the
complex Mo(CO)4 –1. X-ray crystals were obtained from
toluene and hexane. IR (cm21, CO): 2014, 1919, 1389,
1877. 1H NMR (CDCl3, d ) 7.24–8.15 (m, Ph), 6.59–6.65
2.4. X-ray crystallography
Crystal, data collection, and refinement parameters are
given in Table 1. The systematic absences in the diffrac-
tion data were consistent with monoclinic space group
C2/c for both 1 and PdCl2 –2, and uniquely consistent for
the orthorhombic space group Pbca for Mo(CO)4 –1.
Structures of 1 and PdCl2 –2 were refined in the cen-
trosymmetric space group which yielded chemically
reasonable and computationally stable results. Semi-em-
pirical absorption correction was applied to the latter set of
PdCl2 –2 and ignored in the others. All three structures
were solved by direct methods, completed by subsequent
Fourier syntheses and refined by full-matrix least-squares
procedures. The compound was found on a two-fold axis
in PdCl2 –2. The phenyl carbons in 1 were refined isotropi-
cally. All other nonhydrogen atoms were refined aniso-
tropically with hydrogen atoms treated as idealized contri-
butions. All software and sources of the scattering factors
are contained in the SHELXTL PLUS (4.2) Library (G.
Sheldrick, Siemens XRD, Madison, WI).
2
(m, Py), 4.55 (d, NCHHP, JHH514.3 Hz)) and 4.35 (d,
NCHHP, 2JHH514.3 Hz). 13C NMR (CDCl3, d ) CO’s:
2
2
216.2 (t, JPC57.0 Hz), 209.8 (t, JPC59.0 Hz); 158.5,
148.0, 138.1, 129.3, 113.7, 106.3, 134.8 (t, JPC513.9 Hz),
131.3 (t, JPC56.7 Hz), 129.3 (t, JPC54.7 Hz), 49.4 (t,
JPC513.2 Hz). 31P NMR (CDCl3, d ) 23.2 (s). Analysis
from calculation for C30H28MoN4O4P2: C, 54.07%; H,
4.23%; N, 8.41%. Found: C, 54.23%; H, 4.02%; N, 8.30%.
2.2.2. PdCl2 [P(Ph)CH2N(Bz)CH2 ]2 , PdCl2 –2
To a flask containing 0.30 g (0.62 mmol) of ligand 2
and 0.21 g (0.62 mmol) of PdCl2 –2PhCN was added 20
ml of methylene chloride. All the solids dissolved immedi-
ately to give a brown solution. After 30 min of stirring, a
thick yellow suspension formed. This was filtered and the
residue washed with cold hexane and dried to give 0.27 g
(65%) of the tan-brown complex PdCl2 –2. X-ray crystals
were obtained from CH2Cl2 /toluene. 1H NMR (CDCl3, d )
7.34–7.50 (m, Ph), 4.37 (s, NCH2Ph), 3.66 (d, NCHHP,
3. Results and discussion
The two parent 1,5-diaza-3,7-diphosphacyclooctanes,
2
2JHH513.6 Hz), 3.60 (dd, NCHHP, JHH513.6 Hz and
[P(Ph)CH2N(2-pyridyl)CH2]2
(ligand
1)
and
2JPH56.1 Hz). 13C NMR data (CDCl3, d ) 136.2, 131.7,
130.1, 129.3, 128.7, 132.4 (JPC53.8 Hz), 129.0 (t, JPC5
5.5 Hz), 125.44 (dd, JPC552.9 and 2.7 Hz), 63.8 (s,
NCH2Ph), 51.4 (m, NCH2P). 31P NMR (CDCl3, d ) 29.2
(s). Analysis from calculation for C30H32Cl2N2P2Pd: C,
54.61%; H, 4.89%; N, 4.29%. Found: C, 54.54%; H,
5.02%; N, 4.24%.
[P(Ph)CH2N(Bz)CH2]2 (ligand 2), were prepared using the
literature methods in moderate yields [11]. Complexes of
these were readily obtained using the respective metal
precursors Mo(CO)4(h2-norbornadiene), PdCl2 –2PhCN,
and NiCl2 –(dimethoxyethane). Isolated products included
yellow Mo(CO)4 –1, orange PdCl2 –2, and purple NiCl2 –2.
All three products were found to be 1:1 complexes by
elemental analyses even when excess metal reagents were
used in their preparations, confirming earlier reports of
monometallic coordination [12–14]. The crystal structures
of ligand 1, Mo(CO)4 –1, and PdCl2 –2 have been de-
termined. We were not able to grow X-ray quality crystals
of the NiCl2 complex of ligand 2. Its paramagnetic nature,
2.2.3. NiCl2 [P(Ph)CH2N(Bz)CH2 ]2 , NiCl2 –2
To a flask containing 0.20 g (0.42 mmol) of ligand 2
and 0.090 g (0.42 mmol) of NiCl2 –dme was added 20 ml
of toluene. After 5 min, the reaction mixture turned into a
purple suspension. After 1 h, this was filtered and the

J.C. Kane et al. / Polyhedron 18 (1999) 1183–1188
1185
Table 1
Crystallographic data for 1, Mo(CO)4 –1 and PdCl2 –2
1
PdCl2 –2
Mo(CO)4 –1
Formula
C26H28N4P2
458.5
C2/c
26.831(6)
10.535(2)
19.576(2)
121.74(2)
4706(2)
8
C30H32Cl2N2P2Pd
659.8
C2/c
22.526(6)
7.972(2)
15.839(5)
98.52(2)
2813(1)
4
C30H28MoN4O4P2
666.4
Pbca
14.983(4)
19.995(7)
19.583(9)
–
5867(4)
8
Formula weight
Space group
˚
a (A)
˚
b (A)
˚
c (A)
b (8)
V (A )
3
˚
Z
D (calc) (g cm23
)
)
1.294
2.07
298
1.558
9.87
238
1.509
5.99
298
m (MoKa) (cm21
Temp (K)
˚
Radiation
MoKa (l50.71073 A)
R(F) (%)
R(wF) (%)
5.59
6.51
3.67
4.89
6.18
8.06
a Quantity minimized5owD2; R5oD/o(Fo); R(w)5oD1 / 2 /o(Fo –w1 / 2), D5u(Fo2Fc)u.
however, suggested a non-planar geometry at the metal
center, consistent with the observed pseudo-tetrahedral
geometry around the nickel vertex of the previously
reported Mo(CO)4[iPr2NPO]4NiBr2 [19].
3.1. Crystal structure of [CH2P(Ph)CH2N(2-pyridyl)]2 ,
ligand 1
The heterocycle was found to adopt the familiar crown
conformation with essentially planar ring nitrogen environ-
ments (Fig. 2). The sum of the bond angles around either
N(1) or N(2) totalled 3598. The two phosphorus lone pairs
are oriented syn to each other, suitable for metal chelation.
Average ring P–C distances and N–C bond lengths were
˚
˚
1.87 A and 1.45 A, respectively. Selected bond distances
and angles are presented in Table 2. For comparison, the
previously reported structure of [P(Ph)CH2N(Ph)CH2]2
has endocyclic angles within 28 of those in 1 [15]. Near
planarity of the ring nitrogen bonding geometry is also
˚
observed. Its average ring P–C bond length of 1.88 A and
˚
N–C length of 1.45 A are essentially analogous. Both
heterocyclic conformations are close to an idealized crown.
3.2. Crystal structure of Mo(CO)4 [P(Ph)CH2N(2-
pyridyl)CH2 ]2 , Mo(CO)4 –1
Unlike several six-coordinate metal complexes of 1,5-
dithiacyclooctane and many 1,5-diazacyclooctane deriva-
tives [8,9], a chair–boat ligand conformation was ob-
served in this complex (Fig. 3). The distorted octahedral
coordination environment around Mo features a com-
pressed P(1)–Mo–P(2) angle of only 74.9(1)8 and cis-P–
Mo–C angles greater than orthogonality ranging from
91.0(3)8 to 101.7(3)8 for P(1)–Mo–C(3). This significant
expansion of the P(1)–Mo–C(3) angle is a direct conse-
quence of the proximity of the P(1)–phenyl group. The
Fig. 2. (a)Molecular structure of [P(Ph)CH2N(2-Py)CH2]2, 1; (b) Crown
conformation of ligand 1.

1186
J.C. Kane et al. / Polyhedron 18 (1999) 1183–1188
Table 2
˚
Selected bond lengths (A) and bond angles (8) for 1
P(1)–C(5)
P(1)–C(16)
P(2)–C(7)
N(1)–C(7)
N(1)–C(36)
N(1)–C(6)
C(5)–P(1)–C(8)
C(8)–P(1)–C(16)
C(6)–P(2)–C(26)
C(7)–N(1)–C(8)
C(8)–N(1)–C(36)
C(5)–N(2)–C(46)
P(1)–C(5)–N(2)
P(2)–C(7)–N(1)
1.876(7)
1.826(4)
1.884(7)
1.444(7)
1.385(9)
1.449(5)
P(1)–C(8)
P(2)–C(6)
P(2)–C(26)
N(1)–C(8)
N(2)–C(5)
N(2)–C(46)
C(5)–P(1)–C(16)
C(6)–P(2)–C(7)
C(7)–P(2)–C(26)
C(7)–N(1)–C(36)
C(5)–N(2)–C(6)
C(6)–N(2)–C(46)
P(2)–C(6)–N(2)
P(1)–C(8)–N(1)
1.862(6)
1.856(6)
1.820(4)
1.459(6)
1.451(7)
1.374(8)
97.2(2)
101.0(3)
101.5(3)
101.0(3)
118.9(5)
118.7(4)
120.9(4)
114.6(4)
114.3(4)
100.4(3)
98.7(3)
121.1(4)
118.4(5)
120.1(4)
113.6(4)
113.2(4)
˚
average Mo–P bond length of 2.49 A is almost identical to
that found in the structure of Mo(CO)4[iPr2NPO]4 [20].
Both ring nitrogens are near planarity with bond angle
sums totalling 3608 and 3578 at N(1) and N(2), respective-
˚
ly. Average ring P–C and N–C distances are 1.86 A and
˚
1.45 A, essentially unchanged from the free ligand values.
The observed shorter cis-Mo–C(carbonyl) bond lengths of
˚
1.98 A (average) compared to trans-Mo–C distances of
˚
2.03 A (average) is well established in metal carbonyl
phosphine structures. Selected bond distances and angles
are listed Table 3.
Chelation of the Mo(CO)4 moiety led to a closing of the
two phosphorus ring atoms from the free ligand value of
˚
˚
3.750(2) A to only 3.023(3) A. The other notable change,
of course, is the flipping of N(1) from the crown into the
chair–boat conformation as manifested in changes of its
ring torsional angles from 85.708 and 291.08 to 270.08
and 67.88, respectively (Table 4).
In solution at ambient temperature, this complex ap-
peared to be either conformationally mobile or in a
structure of higher symmetry with ring methylenes appear-
ing as a single AB system in its 1H NMR spectrum.
2
Interestingly, no discernable JPH coupling was observed.
Its 13Ch1Hj NMR spectrum contained a single virtual
triplet at 49.4 ppm assignable to four equivalent methylene
ring carbons.
Fig. 3. (a) Core structure of Mo(CO)4 –[P(Ph)CH2N(2-Py)CH2]2,
Mo(CO)4 –1; (b) molecular structure of Mo(CO)4 –1.
The same chair–boat coordination ring conformation
was also found in the solid-state structures of Cu(I) and
Pt(II) complexes of related 1,5-diaza-3,7-diphos-
phacyclooctanes [12–14]. In CuI(pyridine)[P(Ph)CH2N( p-
tolyl)CH2]2, however, one of the ring nitrogens is more
pyramidal with bond angles totalling only 3448. The other
ring nitrogen bond angles do add up to a near-planar value
of 3548. The P–Cu–P angle is 86.78(6)8, far short of the
ideal tetrahedral angle, but still considerably larger than
the P–Mo–P angle in Mo(CO)4 –1. The shorter Cu–P
3.3. Crystal structure of PdCl2 [P(Ph)CH2N(Bz)CH2 ]2 ,
PdCl2 –2
The heterocyclic ligand was found in a highly distorted
crown conformation with both nitrogens flattened towards
the four ring-carbon plane. These ring nitrogens are only
˚
˚
0.223 A from the least-squares plane of these ring-carbons,
distance of 2.26 A compared to the average Mo–P bond
˚
˚
whereas the phosphorus atoms are a full 1.123 A out of
length of 2.49 A is consistent with the discrepancy in
this plane (Fig. 4). Although not previously observed in
P–M–P angles.

J.C. Kane et al. / Polyhedron 18 (1999) 1183–1188
1187
Table 3
Selected bond lengths (A) and bond angles (8) for Mo(CO)4 –1
˚
Mo–P(1)
Mo–C(1)
Mo–C(3)
N(1)–C(7)
N(1)–C(36)
N(2)–C(6)
P(1)–C(5)
P(1)–C(16)
2.480(3)
2.013(13)
1.978(12)
1.451(12)
1.392(13)
1.446(12)
1.863(10)
1.802(10)
1.868(10)
74.9(1)
Mo–P(2)
Mo–C(2)
Mo–C(4)
N(1)–C(8)
N(2)–C(5)
N(2)–C(46)
P(1)–C(8)
P(2)–C(6)
2.492(3)
1.988(11)
2.041(13)
1.439(12)
1.455(11)
1.392(14)
1.861(10)
1.850(10)
1.823(11)
91.0(3)
P(2)–C(7)
P(2)–C(26)
P(1)–Mo–P(2)
P(2)–Mo–C(1)
P(2)–Mo–C(2)
P(1)–Mo–C(3)
C(1)–Mo–C(3)
P(1)–Mo–C(4)
C(1)–Mo–C(4)
C(3)–Mo–C(4)
C(7)–N(1)–C(36)
C(5)–N(2)–C(6)
C(6)–N(2)–C(46)
Mo–P(1)–C(8)
Mo–P(1)–C(16)
C(8)–P(1)–C(16)
Mo–P(2)–C(7)
Mo–P(2)–C(26)
C(7)–P(2)–C(26)
N(2)–C(6)–P(2)
N(1)–C(8)–P(1)
P(1)–Mo–C(1)
P(1)–Mo–C(2)
C(1)–Mo–C(2)
P(2)–Mo–C(3)
C(2)–Mo–C(3)
P(2)–Mo–C(4)
C(2)–Mo–C(4)
C(7)–N(1)–C(8)
C(8)–N(1)–C(36)
C(5)–N(2)–C(46)
Mo–P(1)–C(5)
C(5)–P(1)–C(8)
C(5)–P(1)–C(16)
Mo–P(2)–C(6)
C(6)–P(2)–C(7)
C(6)–P(2)–C(26)
N(2)–C(5)–P(1)
N(1)–C(7)–P(2)
93.1(3)
92.3(3)
101.7(3)
86.6(5)
87.7(3)
167.1(2)
90.6(5)
176.6(3)
91.1(5)
95.6(3)
92.8(4)
116.6(8)
118.3(8)
120.9(8)
112.5(3)
102.3(4)
103.7(4)
113.9(3)
99.6(4)
170.5(5)
84.5(5)
125.1(8)
118.4(7)
117.3(8)
113.4(3)
122.6(3)
99.9(4)
115.0(3)
118.6(3)
100.8(5)
113.0(7)
113.4(6)
106.6(5)
113.7(6)
111.6(7)
1,5-diaza-3,7-diphosphacyclooctane complexes [12–14],
this coordinating ring conformation was found in the
related tetraphosphoxane complex PdCl2[iPr2NPO]4 which
had all six non-coordinating atoms of the P4O4 ring within
˚
0.01 A of planarity [21]. Upon metal chelation, the ligand
Fig. 4. (a) Molecular structure of PdCl2 –[P(Ph)CH2N(Bz)CH2]2, PdCl2 –
2; (b) ligand conformation in PdCl2 –2.
2 phosphorus atoms are brought together to a separation of
only 2.963 A. Ring torsional angles reflect this chelating
˚
conformation compared to the two other structures de-
scribed in this study (Table 4). At both ring N’s, the
torsional angles are substantially smaller in magnitude with
values of 264.08 and 60.88 than those for ligand 1.
The near square-planar palladium coordination sphere
contains a distorted P–Pd–P angle of 82.5(1)8 and Cl–Pd–
Cl angle of 91.9(1)8. The average Pd–Cl and Pd–P bond
˚
˚
lengths of 2.362(1) A and 2.247(1) A are unexceptional.
˚
Again, average ring P–C and N–C distances of 1.89 A and
1.45 A, respectively, are very similar to those of related
heterocycles and complexes. Interestingly, both ring nitro-
gens have bonding environments almost midway between
˚
Table 4
Comparison of ring torsional angles (8) for 1, Mo(CO)4 –1 and PdCl2 –2
1
Mo(CO)4 –1
PdCl2 –2
C(8)–P(1)–C(5)–N(2)
C(5)–P(1)–C(8)–N(1)
C(7)–N(1)–C(8)–P(1)
C(8)–N(1)–C(7)–P(2)
C(6)–P(2)–C(7)–N(1)
C(7)–P(2)–C(6)–N(2)
C(5)–N(2)–C(6)–P(2)
C(6)–N(2)–C(5)–P(1)
100.5
293.7
85.7
291.0
100.5
294.7
86.2
C(8)–P(1)–C(5)–N(2)
C(5)–P(1)–C(8)–N(1)
C(7)–N(1)–C(8)–P(1)
C(8)–N(1)–C(7)–P(2)
C(6)–P(2)–C(7)–N(1)
C(7)–P(2)–C(6)–N(2)
C(5)–N(2)–C(6)–P(2)
C(6)–N(2)–C(5)–P(1)
103.9
248.5
270.0
67.8
51.5
2110.8
66.6
C(3A)–P–C(1)–N
111.0
2106.3
60.8
264.0
111.0
2106.3
60.8
264.0
C(1)–P–C(3A)–N(0A)
C(1A)–N(0A)–C(3A)–P
C(3A)–N(0A)–C(1A)–P(0A)
C(3)–P(0A)–C(1A)–N(0A)
N–C(3)–P(0A)–C(1A)
C(1)–N–C(3)–P(0A)
290.5
263.3
C(3)–N–C(1)–P(0A)

1188
J.C. Kane et al. / Polyhedron 18 (1999) 1183–1188
Table 5
Supplementary data
˚
Selected bond lengths (A) and bond angles (8) for PdCl2 –2
Pd–Cl
Pd–ClA
P–C(1)
P–C(3A)
N–C(2)
Cl–Pd–P
P–Pd–ClA
P–Pd–PA
Pd–P–C(1)
C(1)–P–C(26)
C(1)–P–C(3A)
C(1)–N–C(2)
C(2)–N–C(3)
N–C(2)–C(16)
2.362(1)
2.362(1)
1.878(3)
1.894(3)
1.469(4)
93.1(1)
Pd–P
Pd–PA
P–C(26)
N–C(1)
2.247(1)
2.247(1)
1.810(3)
1.456(4)
1.439(4)
91.9(1)
Tables of X-ray experimental details and crystallo-
graphic data, all atomic coordinates, anisotropic thermal
parameters, and bond distances and angles for the struc-
tures of ligand 1 (Deposition No. 103281), Mo(CO)4 –1
(Deposition No. 103282), and PdCl2 –2 (Deposition No.
103295) have been deposited at the Crystallographic Data
Center (CCDC, Cambridge, UK).
N–C(3)
Cl–Pd–ClA
Cl–Pd–PA
ClA–Pd–PA
Pd–P–C(26)
Pd–P–C(3A)
C(26)–P–C(3A)
C(1)–N–C(3)
P–C(1)–N
N–C(3)–PA
172.9(1)
82.5(1)
172.9(1)
93.1(1)
111.4(1)
107.4(1)
104.4(1)
116.6(2)
113.6(2)
112.6(3)
119.8(1)
109.8(1)
102.7(1)
113.1(2)
116.0(2)
117.1(2)
References
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Other selected bond lengths and angles are listed in Table
5.
1
At ambient temperature, the solution H NMR spectrum
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2
2JAB513.6 Hz and JPB56.1 Hz. This is not inconsistent
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