Copper and palladium complexes of 2-(diphenylphosphino)-N, N-dimethylbenzylamine and its selenide derivative

Article abstract of DOI:10.1016/j.poly.2013.06.036

The synthesis of 2-(diphenylphosphino)-N, N-dimethylbenzylamine, {Ph ₂P(C₆H₄CH₂NMe_2-o)} (1) and its chalcogenide derivatives, {Ph2P(E)(C₆H₄CH ₂NMe_2-o)} (E=

Full text of DOI:10.1016/j.poly.2013.06.036

Polyhedron 62 (2013) 203–207
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Polyhedron
journal homepage: www.elsevier.com/locate/poly
Copper and palladium complexes of 2-(diphenylphosphino)-N,
N-dimethylbenzylamine and its selenide derivative
Guddekoppa S. Ananthnag a, Namepalli Edukondalu a, Joel T. Mague b, Maravanji S. Balakrishna a,
⇑
a Phosphorus Laboratory, Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400 076, India
b Department of Chemistry, Tulane University, New Orleans, LA 70118, USA
a r t i c l e i n f o
a b s t r a c t
Article history:
The synthesis of 2-(diphenylphosphino)-N,N-dimethylbenzylamine, {Ph2P(C6H4CH2NMe2-o)} (1) and its
chalcogenide derivatives, {Ph2P(E)(C6H4CH2NMe2-o)} (E = O, 2; S, 3; Se, 4) were described. The reaction
Received 4 June 2013
Accepted 21 June 2013
Available online 2 July 2013
of 1 with [Pd(g g
3-C3H5)Cl]2 affords a cationic complex [{Ph2P(C6H4CH2NMe2-o)}Pd( 3-C3H5)][OTf] (5) in
good yield. The treatment of 1 with copper halides in 1:1 M ratio afforded complexes of the type
[{Ph2P(C6H4CH2NMe2-o)}(CuX)]2 (X = Br, 6; X = I, 7). Similar reactions between copper halides and
Ph2RP(Se) (4) produced [{Ph2P(Se)(C6H4CH2NMe2-o)}(CuX)]2 (X = Br, 8; X = I, 9). The copper complex 7
upon treatment with 2,20-bipyridine and 1,10-phenanthroline produced mixed ligand complexes
[{Ph2P(C6H4CH2NMe2-o)}Cu(2,2’-bpy)]I (10) and [{Ph2P(C6H4CH2NMe2-o)}Cu(1,10-phen)]I (11), respec-
tively. Single crystal X-ray structures of 7 and 9 are described.
Keywords:
P,N ligands
Phosphorus selenide
Bidentate
Chelating complexes
Palladium
Ó 2013 Elsevier Ltd. All rights reserved.
Copper
1. Introduction
through chalcogens and pendant amine group to form seven-mem-
bered chelate complexes. Herein, we report the palladium(II) and
The phosphorus(III) based hemilabile ligands containing N, O or
S donor atoms attracted much attention in recent years mainly due
to their applications in a variety of organic transformations [1].
These ligand systems were successfully employed in Suzuki–Miya-
ura [2,3], Mizoroki–Heck [4] cross coupling reactions, hydrofor-
mylation [5], hydrogenation [6–8] and many other catalytic
reactions [9–11]. The difference in the coordination properties of
two donor groups is responsible for the distinct interaction
between donor atoms and the metal centers [12,13]. The soft donor
atom forms stronger bond with soft metal centers, whereas the
labile hard donor site provides temporarily coordinative saturation
to metal centre and also detaches as and when it is required during
catalytic reactions. The P,N bidentate ligands are important class of
hemilabile ligands as they can exhibit either chelating mode of
coordination or bind to the metal centres in a monodentate fashion
via phosphorus leaving the nitrogen atom uncoordinated [14–17].
The coordination chemistry of 2-(diphenylphosphino)-N,
N-dimethylbenzylamine is interesting due to its versatile coordi-
nation behavior [18,19]. Further, oxidation of phosphorus atom
in 2-(diphenylphosphino)-N,N-dimethylbenzylamine by chalco-
gens can furnish N^O, N^S or N^Se type of heterodifunctional
ligands [20]. These ligand systems can coordinate to metal centre
copper(I) complexes of 2-(diphenylphosphino)-N,N-dimethylben-
zylamine and its selenide derivative.
2. Results and discussion
2.1. Oxidation reactions of 2-(diphenylphosphino)-N,N-
dimethylbenzylamine (1)
2-(Diphenylphosphino)-N,N-dimethylbenzylamine (1) was
prepared by reacting in situ generated o-lithiated amine (LiC6H4
CH2NMe2) with PPh2Cl [19,21]. The reaction of 1 with aqueous
H2O2 in tetrahydrofuran at room temperature gave 2-(diphenyl-
phosphoryl)-N,N-dimethylbenzylamine (2). Similar reaction of 1
with elemental sulfur or selenium [22] in toluene under refluxing
conditions afforded Ph2P(E)(C6H4CH2NMe2-o) (E = S, 3; Se, 4) in
good yield. The 31P NMR spectra of chalcogenides 2–4 showed
sharp singlets at 33.7, 41.9 and 31.2 ppm, respectively, with the
selenide derivative 4 exhibiting characteristic selenium satellite
peaks with a 1JPSe coupling of 724.6 Hz. The molecular composition
and structures of compounds 2–4 were further confirmed by 1H
NMR data and HRMS analysis.
Compound 1 containing both trivalent phosphorus and NMe2
group is an ideal ligand for transition metal chemistry. The reaction
of 1 with [Pd(
acetonitrile followed by the addition of AgOTf afforded a cationic
complex [{Ph2P(C6H4CH2NMe2-o)}Pd(
3-C3H5)][OTf] (5) in good
g
3-C3H5)Cl]2 in a mixture of dichloromethane and
⇑
Corresponding author. Fax: +91 22 5172 3480/2576 7152.
E-mail
addresses:
krishna@chem.iitb.ac.in,
msb_krishna@iitb.ac.in
(M.S. Balakrishna).
g
0277-5387/$ - see front matter Ó 2013 Elsevier Ltd. All rights reserved.
http://dx.doi.org/10.1016/j.poly.2013.06.036

204
G.S. Ananthnag et al. / Polyhedron 62 (2013) 203–207
1. [Pd(η3-C3H5)Cl]2
2. AgOTf
CH2Cl2/CH3CN
Me2
N
NMe2
1/8 E8, toluene, Δ, 10 h
or H2O2, THF, rt, 10 h
NMe2
E
Pd
OTf
P
PPh2
1
P
Ph2
2 E = O
3 E = S
4 E = Se
Ph2
5
CuX
CH2Cl2/CH3CN
CuX
CH2Cl2/CH3CN
Me2
Ph2
P
Ph2
P
Me2
N
X
S
e
X
X
N
Cu
Cu
Cu
Cu
X
P
N
Se
P
N
Ph2
Me2
Ph2
Me2
8 X = Br
6 X = Br
7 X = I
9
X = I
Scheme 1.
yield (Scheme 1). The mass spectrum of 5 shows a peak at m/z
466.1 for [M–OTf] ion. The 31P NMR spectrum of the complex 5
presents a sharp singlet at 21.9 ppm. The presence of coordinated
allyl group was confirmed by its 1H NMR spectrum.
rahedral geometry with internal bond angles ranging from 96.82(11)
to 122.65(4)°. The Cu2I2 rhombic units in both the molecules of 7 are
planar. The Cu–I bond distances in asymmetric molecule are in the
range of 2.5742(11) ꢀ 2.7077(10) Å, whereas in the symmetric mol-
ecule the average Cu–I bond distance is 2.640 Å. The Cu–P1, Cu2–P2
and Cu3–P3 bond distances are 2.2403(14), 2.2334(14) and
2.2349(14) Å, respectively. The Cu–N bond distances in 7 are in the
range of 2.180(4) ꢀ 2.201(4) Å.
Copper(I) halides, in particular cuprous iodide, display a wide
range of structures when coordinated to phosphorus based ligands
[23–27]. The reaction of copper halides with 1 in 1:1 M ratio affor-
ded the complexes [{Ph2P(C6H4CH2NMe2-o)}(CuX)]2 (X = Br, 6;
X = I, 7) with ligand exhibiting chelating mode of coordination.
The 31P NMR spectra of compounds 6 and 7 consist of broad sing-
lets at ꢀ16.2 and ꢀ14.5 ppm, respectively. The mass spectrum of
complex 7 shows a molecular ion peak at m/z 1021.17, whereas
6 show a peak at m/z 845.22 due to the cation [M–Br]+. The
reaction of copper halides with 4 in 1:1 mixture of acetonitrile
and dichloromethane yielded complexes of the type [{Ph2P(Se)
(C6H4CH2NMe2-o)}(CuX)]2 (X = Br, 8; X = I, 9). The 31P NMR spectra
of compounds 8 and 9 show broad singlets at 23.2 and 26.4 ppm,
The complex 9 was crystallized from a mixture of dichloro-
methane and petroleum ether solution at room temperature. The
crystal structure of 9 reveals that the copper centers are tetrahe-
drally coordinated to nitrogen, selenium and two bridging iodide
ions. The average Cu–I bond distance is 2.630 Å which is compara-
ble to that of complex 7. The seven membered rings in 9 adopt the
distorted chair conformations. The Cu1–Se1 bond length
[2.4298(17) Å] in 9 is shorter than that found in [Ph3PSeCu
(
(
l
j
-Br)NCCH3]2 [2.459(2) Å] [28] and [Cu(j2-P,P0-DPEphos)
1
respectively, with 9 showing JPSe coupling of 650.2 Hz. Due to
2-P,Se-DPEphos-Se)][BF4] [2.5877(6) Å] [29].
1
broad signal, JPSe was not observed in case of 8. The 1H NMR
and elemental analysis data are consistent with the proposed
structures. The structures of 7 and 9 have been confirmed by single
crystal X-ray diffraction studies.
3. Conclusions
Copper(I) and palladium(II) complexes of 2-(diphenylphos-
phino)-N,N-dimethylbenzylamine (1) have been synthesized. The
binuclear copper complex upon treatment with pyridyl ligands
afforded mononuclear mixed ligand complexes. The selenide 4
coordinates to the copper centre through selenium and nitrogen
atoms in a chelating fashion to form a seven membered ring. Further
catalytic reactions are under active investigations in our laboratory.
The mixed donor complexes, [{Ph2P(C6H4CH2NMe2-o)}Cu
(2,2’-bpy)]I (10) and [{Ph2P(C6H4CH2NMe2-o)}Cu(1,10-phen)]I
(11) were synthesized in good yield by the reactions of 7 with
2,2’-bipyridine or 1,10-phenanthroline in 1:2 M ratios at room
temperature (Scheme 2). The yellow crystalline compounds 10
and 11 are characterized by 31P, 1H NMR spectra and elemental
analyses. The 31P NMR spectra of complexes 10 and 11 consist of
broad singlets at ꢀ14.9 and ꢀ9.5 ppm, respectively.
4. Experimental section
2.2. Molecular structures of complexes, [{Ph2P(C6H4CH2NMe2-
o)}(CuI)]2 (7) and [{Ph2P(Se)(C6H4CH2NMe2-o)}(CuI)]2 (9)
4.1. General procedures
All manipulations were performed using standard Schlenk tech-
niques under nitrogen atmosphere unless otherwise stated. All the
solvents were purified by conventional procedures and distilled
prior to use. The compounds, 2-(diphenylphosphino)-N,N-dimeth-
The perspective views of molecular structures of 7 and 91along
with the atom labeling schemes are shown in Figs. 1 and 2. The com-
pounds 7 and 9 crystallize in triclinic and monoclinic crystal sys-
tems, respectively. The unit cell of binuclear copper complex 7
consists of two independent molecules with one of them possessing
center of symmetry. The copper centers in 7 display a distorted tet-
ylbenzylamine [19], [Pd(g
3-C3H5)Cl]2 [30] and CuBr [31] were pre-
pared according to the published procedures. Other chemicals
were obtained from commercial sources and purified prior to use.
1
ꢀ
Crystal data for 7: C42H44Cu2I2N2P2, Mw = 1019.61, Triclinic, P1 (No. 02),
4.2. Instrumentation
a = 14.090(3) Å, b = 13.945(2) Å c = 18.698(2) Å V = 3300.7(8) Å3, Z = 3, qcalc
=
1.539 gcmꢀ3 ) = 2.471 mmꢀ1, F(000) = 1512, S = 1.17, T = 100 K. A total of
, l (Mo Ka
The NMR spectra were recorded at the following frequencies:
400 MHz (1H), and 162 MHz (31P) (d in ppm) using Bruker AV
400 spectrometer. The 31P NMR spectra were acquired using broad
band decoupling. The spectra were recorded in CDCl3 (or DMSO-d6)
solutions with CDCl3 (or DMSO-d6) as an internal lock; chemical
shifts of 1H spectra are reported in ppm downfield from TMS, used
111650 reflections (3.0 < h < 25.0) were processed of which 16600, were unique
(Rint = 0.044). The final wR value was 0.111 (all data) and R = 0.0502 [I > 2r(I)]. Crystal
data for 9:
a = 12.510(5) Å, b = 13.372(6) Å c = 12.609(6) Å V = 2067.1(16) Å3, Z = 2, qcalc
1.892gcmꢀ3 ) = 4.394 mmꢀ1, F(000) = 1144, S = 0.95, T = 100 K. A total of
(Mo K
C42H44Cu2I2N2P2Se2, Mw = 1177.53, Monoclinic, P2–1/n (No. 14),
=
,
l
a
28997 reflections (3.0 < h < 25.0) were processed of which 4245, were unique
(Rint = 0.094). The final wR value was 0.1732 (all data), R = 0.0633 [I > 2r(I)].

G.S. Ananthnag et al. / Polyhedron 62 (2013) 203–207
205
Ph2
Ph2
P
Me2
Ph2
P
P
I
N
N
N
N
N
Cu
Cu
1,10-phen
CH2Cl2
I
I
Cu
Cu
2,2'-bipy
CH2Cl2
I
P
N
N
N
Ph2
Me2
Me2
Me2
7
10
11
Scheme 2.
Fig. 1. The molecular structure of [{Ph2P(C6H4CH2NMe2-o)}(CuI)]2 (7). All hydrogen atoms are omitted for clarity. Thermal ellipsoids are drawn at 50% probability level.
Selected bond distances [Å]: Cu1–I1, 2.6000(11); Cu1–I2, 2.7077(10); Cu1–P1, 2.2403(14); Cu1–N1, 2.201(4); Cu2–I1, 2.6722(10); Cu2–I2, 2.5742(11); Cu2–P2, 2.2334(14);
Cu2–N2, 2.180(4); 2.180(4); Cu3–I3, 2.6806(13); Cu3–P3, 2.2349(14); Cu3–N3, 2.186(4). Selected bond angles [°]: Cu1–I1–Cu2, 67.01(2); P1–Cu1–N1, 97.01(11); P1–Cu1–I1,
122.65(4); P1–Cu1–I2, 106.76(4); I1–Cu1–I2, 112.07(3); Cu2–P2–N2, 96.82(11); I3–Cu3–N3, 110.36(11).
Fig. 2. The molecular structure of [{Ph2P(Se)(C6H4CH2NMe2-o)}(CuI)]2 (9). All hydrogen atoms are omitted for clarity. Thermal ellipsoids are drawn at 50% probability level.
Selected bond distances [Å]: Cu1–I1, 2.6433(17); Cu1i–I1, 2.6274(16); Cu1–Se1, 2.4298(17); P1–Se1, 2.119(2); Cu1–N1, 2.145(7). Selected bond angles [°]: Cu1–I1–Cu1i,
59.46(3); Cu1–Se1–P1, 103.72(7); I1–Cu1–Se1, 99.76(4); I1–Cu1–N1, 108.68(18); I1–Cu1–I1i, 120.54(4); Se1–Cu1–N1, 108.65(17); I1i–Cu1–Se1, 112.15(4); Se1–P1–C1,
110.6(3).
as an internal standard. The chemical shifts of 31P{1H} NMR spectra
are referred to 85% H3PO4 used as an external standard. The
microanalyses were performed using a Carlo Erba Model 1112
elemental analyzer. Mass spectra were recorded in Waters Q-Tof
micro (YA-105). The melting points were observed in capillary
tubes and are uncorrected.
4.3. Synthesis of Ph2P(O)(C6H4CH2NMe2-o) (2)
A 30% solution of H2O2 (0.008 g, 0.235 mmol) in 10 mL of THF
was added dropwise to solution of ligand 1 (0.07 g, 0.219 mmol)
in the same solvent (6 mL) at room temperature. The reaction mix-
ture was stirred for 10 h. The solvent was removed under vacuum,

206
G.S. Ananthnag et al. / Polyhedron 62 (2013) 203–207
to get product as colorless viscous liquid. Yield: 93% (0.068 g).
HRMS Calc. for C21H23NPO (M+H): 336.1517. Found: 336.1515.
1H NMR (400 MHz, CDCl3): d 8.43–7.00 (m, Ph, 14H), 5.03 (s, CH2,
2H), 3.29 (s, NMe2, 6H). 31P{1H} NMR (162 MHz, CDCl3): d 33.7 (s).
NMR (400 MHz, CDCl3): d 7.53–6.82 (m, Ar, 28H), 3.51 (s, CH2,
4H), 2.37 (s, NMe2, 12H). 31P{1H} NMR (162 MHz, CDCl3): d ꢀ14.5
(br s). MS (EI): m/z 1021.17 [M+1]+.
4.9. Synthesis of [{Ph2P(Se)(C6H4CH2NMe2-o)}(CuBr)]2 (8)
4.4. Synthesis of Ph2P(S)(C6H4CH2NMe2-o) (3)
A solution of CuBr (0.0173 g, 0.12 mmol) in 10 mL of acetoni-
trile was added dropwise to a solution of 4 (0.048 g, 0.12 mmol)
in 10 mL of dichloromethane at room temperature. The reaction
mixture was stirred for 4 h. The solvent was removed under re-
duced pressure to obtain 8 as a brown crystalline solid. Yield:
82% (0.054 g). Mp: >195 °C (dec). Anal. Calc. for C42H44Cu2Br2N2P2-
Se2ꢁCH3CN: C, 46.99; H, 4.21; N, 3.74. Found: C, 46.77; H, 4.10; N,
3.79%. 1H NMR (400 MHz, CDCl3) d 7.73–7.02 (m, Ar, 28H), 3.43
(s, CH2, 4H), 2.46 (s, NMe2, 12H). 31P{1H} NMR (162 MHz, CDCl3):
d 23.2 (br s).
A mixture of elemental sulfur (0.008 g, 0. 25 mmol) and 1
(0.077 g, 0.241 mmol) in toluene (20 mL) was refluxed for 10 h.
The reaction mixture was allowed to cool to room temperature;
solvent was removed under reduced pressure. The sulfide 3 was
isolated as an yellow viscous liquid. Yield: 89% (0.075 g). HRMS
Calc for C21H23NPS (M+H): 352.1289. Found: 352.1299. 1H NMR
(400 MHz, CDCl3): d 7.91–6.88 (m, Ph, 14H), 3.61 (s, CH2, 2H),
1.91 (s, NMe2, 6H). 31P{1H} NMR (162 MHz, CDCl3): d 41.9 (s).
4.5. Synthesis of Ph2P(Se)(C6H4CH2NMe2-o) (4)
4.10. Synthesis of [{Ph2P(Se)(C6H4CH2NMe2-o)}(CuI)]2 (9)
A mixture of elemental selenium (0.02 g, 0.252 mmol) and 1
(0.1 g, 0.251 mmol) in toluene (30 mL) was refluxed for 10 h. The
reaction mixture was allowed to cool to room temperature and fil-
tered through Celite. The solvent was removed under reduced
pressure to give 4 as an off-white powder. Yield: 91% (0.112 g).
Anal. Calc. for C21H23NPSe: C, 63.14; H, 5.55; N, 3.50. Found: C,
63.28; H, 5.43; N, 3.37%. 1H NMR (400 MHz, CDCl3): d 7.88–6.86
(m, Ph, 14H), 3.70 (s, CH2, 2H), 2.01 (s, NMe2, 6H). 31P{1H} NMR
This was synthesized by a procedure similar to that of 8 using
CuI (0.029 g, 0.151 mmol) and 4 (0.06 g, 0.151 mmol). Yield: 76%
(0.068 g). Mp: >219 °C (dec). Anal. Calc. for C42H44Cu2I2N2P2Se2:
C, 42.79; H, 3.77; N, 2.38. Found: C, 42.54; H, 3.76; N, 2.43%. 1H
NMR (400 MHz, CDCl3): d 7.82–7.06 (m, Ph, 28H), 3.50 (s, CH2,
4H), 2.40 (s, NMe2, 12H). 31P{1H} NMR (162 MHz, CDCl3): d 26.1
1
(br s, JPSe = 650.2).
1
(162 MHz, CDCl3): d 31.2 (s, JPSe = 724.6 Hz).
4.11. Synthesis of [{Ph2P(C6H4CH2NMe2-o)}Cu(2,2’-bpy)]I (10)
4.6. Synthesis of [{Ph2P(C6H4CH2NMe2-o)}Pd(
g
3-C3H5)](OTf) (5)
To a suspension of 7 (0.0304 g, 0.029 mmol) in dichloromethane
(10 mL), was added 2,2’-bipyridine (0.0093 g, 0.059 mmol) also in
dichloromethane (5 mL). After 4 h, the clear yellow solution was
dried under reduced pressure to afford 10 as an yellow solid. Yield:
78% (0.031 g). Mp: 150–152 °C. Anal. Calc. for C31H30CuIN3PꢁCH2-
Cl2: C, 51.26; H, 4.30; N, 5.60. Found: C, 51.15; H, 4.24; N, 5.48%.
1H NMR (400 MHz, CDCl3): d 7.55–6.98 (m, Ar, 22H), 3.54 (s, CH2,
2H), 2.39 (s, NMe2, 6H).31P{1H} NMR (162 MHz, CDCl3): d ꢀ14.9
(br s).
To a solution of [Pd(
g
3-C3H5)Cl]2 (0.029 g, 0.076 mmol) in 10 mL
of dichloromethane was added dropwise 1 (0.05 g, 0.158 mmol) in
the same solvent (5 mL) at room temperature. The reaction mix-
ture was stirred for 2 h. AgOTf (0.041 g, 0.159 mmol) in CH3CN
(5 mL) was added to the reaction mixture and stirring was contin-
ued for another 2 h. AgCl precipitate formed was removed by filtra-
tion. The solvents were removed under vacuum to get 5 as an
yellow crystalline solid. Yield: 84% (0.066 g). Mp: >120 °C (dec).
Anal. Calc. for C25H27F3NO3PPdS: C, 48.75; H, 4.42; N, 2.27; S,
5.21. Found: C, 48.45; H, 4.43; N, 2.37; S, 4.98%. 1H NMR
(400 MHz, CDCl3): d 7.59–6.96 (m, Ar, 14H), 6.05 (m, allyl, 1H),
4.95 (br s, allyl, 1H), 4.21 (br s, allyl, 1H) 3.61 (s, CH2, 2H), 3.24
(m, allyl, 2H), 2.90 (s, NMe2, 6H). 31P{1H} NMR (162 MHz, CDCl3):
d 22.0 (s).
4.12. Synthesis of [{Ph2P(C6H4CH2NMe2-o)}Cu(1,10-phen)]I (11)
This was synthesized by a procedure similar to that of 10 using
7
(0.034 g, 0.033 mmol) and 1,10-phenanthorline (0.012 mg,
0.066 mmol). Yield: 75% (0.0345 g). Mp: 197–200 °C. Anal. Calc.
for C33H30CuIN3Pꢁ0.5CH2Cl2: C, 54.93; H, 4.27; N, 5.74. Found: C,
54.67; H, 4.46; N, 5.83%. 1H NMR (400 MHz, CDCl3) d 7.67–6.92
(m, Ar, 22H), 3.61 (s, CH2, 2H), 2.29 (s, NMe2, 6H). 31P{1H} NMR
(162 MHz, CDCl3): d ꢀ9.5 (br s).
4.7. Synthesis of [{Ph2P(C6H4CH2NMe2-o)}(CuBr)]2 (6)
To a solution of CuBr (0.0135 g, 0.094 mmol) in 10 mL of aceto-
nitrile was added dropwise 1 (0.03 g, 0.094 mmol) in dichloro-
methane (5 mL) at room temperature. The reaction mixture was
stirred for 4 h. The solvent was removed under reduced pressure
to get 6 as a pale yellow solid. Analtyically pure product of 6 was
obtained by recrystallizing the crude product in a 1:2 mixture of
dichloromethane and petroleum ether. Yield: 81% (0.035 g). Mp:
158–160 °C. Anal. Calc. for C42H44Cu2Br2N2P2: C, 54.66; H, 4.80;
N, 3.03. Found: C, 54.95; H, 4.85; N, 2.88%. 1H NMR (400 MHz,
CDCl3): d 7.52–6.83 (m, Ar, 28H), 3.50 (s, CH2, 4H), 2.42 (s, NMe2,
12H). 31P{1H} NMR (162 MHz, CDCl3): d ꢀ16.2 (br s). MS (EI): m/z
845.22 [M–Br]+.
4.13. X-ray Crystallography
Crystals of each of the compounds 7 and 9 suitable for X-ray
crystal analysis were mounted on a Cryoloop with a drop of Par-
atone oil and placed in the cold nitrogen stream of the Kryoflex
attachment of the Bruker APEX CCD diffractometer. A full sphere
of data was collected using three sets of 606 scans in
x (0.3° per
scan) at = 0, 120, and 240° using the SMART [32] software package,
u
or the APEX2 program suite. The raw data were reduced to F2 values
using the SAINT + software [33], and a global refinement of unit cell
parameters, using about 2332–2779 reflections chosen from the
full data set, were performed. Multiple measurements of equiva-
lent reflections provided the basis for an empirical absorption cor-
rection as well as a correction for any crystal deterioration during
the data collection (SADABS [34]). The structure of 7 was solved by
direct methods, whereas the positions of the heavy atoms were ob-
tained from a sharpened Patterson function in case of compound 9.
4.8. Synthesis of [{Ph2P(C6H4CH2NMe2-o)}(CuI)]2 (7)
This was synthesized by a procedure similar to that of 6 using
CuI (0.04 g, 0.21 mmol) and 1 (0.067 g, 0.21 mmol). Yield: 76%
(0.089 g). Mp: 216–220 °C. Anal. Calc. for C42H44Cu2I2N2P2ꢁ2CH3CN:
C, 50.18; H, 4.58; N, 5.09. Found: C, 49.98; H, 4.42; N, 5.13%. 1H

G.S. Ananthnag et al. / Polyhedron 62 (2013) 203–207
207
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Acknowledgments
We are grateful to the Department of Science and Technology
(DST), New Delhi, for financial support of this work through Grant
SR/S1/IC-17/2010. GSA thanks CSIR, New Delhi, for a Research
Fellowship (SRF). We also thank the Department of Chemistry
Instrumentation Facilities, IIT Bombay, for spectral and analytical
data and JTM thanks the Louisiana Board of Regents for the
purchase of the CCD diffractometer and the Chemistry Department
of Tulane University for support of the X-ray laboratory.
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Appendix A. Supplementary data
CCDC 938540 and 938541 contain the supplementary crystallo-
graphic data for 7 and 9. These data can be obtained free of charge
via http://www.ccdc.cam.ac.uk/conts/retrieving.html, or from the
Cambridge Crystallographic Data Centre, 12 Union Road,
Cambridge CB2 1EZ, UK; fax: (+44) 1223-336-033; or e-mail:
deposit@ccdc.cam.ac.uk.
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