Synthesis and X-ray single crystal structures of copper(I) complexes: Cu(S2PiBu2)·(PMe3) 3 and Cu(S2PiBu2)·(PPh3) 2

Article abstract of DOI:10.1016/S0020-1693(02)01020-4

Two new copper(I) complexes Cu(S₂PⁱBu₂)·(PMe₃) ₃ (1) and Cu(S₂PⁱBu₂)·(PPh₃) ₂ (2) have been synthesised and characterised by spectroscopic and X-ray crystallographic methods. Both compounds are monomers in the solid state where copper is four co-ordinate and the co-ordination geometry is based on a distorted tetrahedron. The dithiophosphinate ligand behaves as a monodentate in compound 1 and bidentate in compound 2. Compound 1 is the only example in Cu(I) complexes with a monodentate dithiophosphinate.

Full text of DOI:10.1016/S0020-1693(02)01020-4

Inorganica Chimica Acta 338 (2002) 245ꢀ248
/
www.elsevier.com/locate/ica
Note
Synthesis and X-ray single crystal structures of copper(I) complexes:
Cu(S2PiBu2)×(PMe3)3 and Cu(S2PiBu2)×
(PPh3)2
/
/
M. Azad Malik a, C. Byrom a, P. O’Brien b,*, M. Motevalli c
a Department of Chemistry, Imperial College of Science, Technology and Medicine, South Kensington, London, SW7 2AZ, UK
b Department of Chemistry, The Manchester Materials Science Centre, Manchester University, Oxford Rd, Manchester, M13 9PL, UK
c Department of Chemistry, Queen Mary and Westfield College, Mile End Road, London, E1 4NS, UK
Received 2 December 2001; accepted 15 April 2002
Abstract
Two new copper(I) complexes Cu(S2PiBu2)×
/
(PMe3)3 (1) and Cu(S2PiBu2)×
/
(PPh3)2 (2) have been synthesised and characterised by
spectroscopic and X-ray crystallographic methods. Both compounds are monomers in the solid state where copper is four co-
ordinate and the co-ordination geometry is based on a distorted tetrahedron. The dithiophosphinate ligand behaves as a
monodentate in compound 1 and bidentate in compound 2. Compound 1 is the only example in Cu(I) complexes with a
monodentate dithiophosphinate.
# 2002 Elsevier Science B.V. All rights reserved.
Keywords: Copper(I); Complexes; Dithiophosphinate; X-ray; Monodentate; Synthesis
1. Introduction
2. Experimental
Copper(I) compounds are of particular interest due to
their potential as precursors for metalꢀorganic vapour
/
2.1. Chemicals
deposition (MOCVD) of copper which has potential
applications in the microelectronic industry [1]. Lewis
base-stabilised (b-diketonate)Cu(I) complexes deposit
highly pure copper films (particularly the (hfac) variety
Dried NaS2P(Bui)2, dry CuCl, PMe3, and PPh3 were
obtained from Aldrich Chemical Co. Ltd. and solvents
were obtained from BDH.
[2ꢀ12].
/
Although several Cu(I) dithiophosphate complexes
have previously been reported, but there are no reports
for the preparation of Cu(I) dithiophosphinates. This
may be due to the difficulty of preparing dithiopho-
sphinate ligands compared to the dithiophosphate
2.2. Physical measurements
NMR spectra were recorded using a Bruker AM250
pulsed Fourier transform instrument. IR spectra were
carried out using Matteson Polaris FT-IR spectrometer
as Nujol mulls, mass spectra were recorded by a
micromass Auto-spec-Q using micromass OPUS soft-
ware. An electron impact energy of 70 eV at 10ꢁ7 Torr
was used to initiate mass fragmentation. M.p.s were
measured in sealed tubes with an electrothermal melting
point apparatus and are uncorrected. Microanalyses
were carried out by the Imperial College London
service.
ligands [13ꢀ19].
/
We report the first synthesis and X-ray crystal single
structure of two novel Cu(I) dithiophosphinate com-
pounds, Cu(S2PiBu2)×
(PPh3)2.
/
(PMe3)3 and Cu(S2PiBu2)×
/
* Corresponding author. Tel.: ꢂ
4616
E-mail address: paul.obrien@man.ac.uk (P. O’Brien).
/
44-161-275 4653; fax: ꢂ44-161-275
/
0020-1693/02/$ - see front matter # 2002 Elsevier Science B.V. All rights reserved.
PII: S 0 0 2 0 - 1 6 9 3 ( 0 2 ) 0 1 0 2 0 - 4

246
M.A. Malik et al. / Inorganica Chimica Acta 338 (2002) 245ꢀ248
/
2.3. Synthesis
2.4. Crystallography
All experiments were carried out under nitrogen (i.e.
air sensitive conditions) at all times.
The intensity data were collected on a CAD-4
˚
diffractometer and Mo Ka radiation (l 0.71069 A)
using vꢁ
meters were determined by least-square refinements on
diffractometer angles 11.055u 514.098 for 25 auto-
/2u scan at 180.0(1) K. The unit cell para-
2.3.1. Cu(S2PiBu2)×
/
(PMe3)3 (1)
/
/
Compound 1 was prepared by a modified method
used for the synthesis of (b-diketonate)Cu(I) [1]. Dry
CuCl (0.85 g, 8.6 mmol) was placed in a flask and dry
C6H6 (30 ml) added. PMe3 (1.96 g, 25.9 mmol) was
added. This mixture was then stirred until it became
clear. Dried NaS2P(Bui)2 (2 g, 8.6 mmol) was added and
the mixture stirred for 2 h to ensure that the reaction
had occurred. The mixture was then filtered and the
filtrate concentrated. Dried C5H12 (10 ml) was then
added and the solution left to recrystallise in the freezer.
Yield: 1.97 g (65.6%), m.p. 55 8C of product was
produced. (Anal. Found: C, 39.9; H, 9.1. Calc.: C,
matically centred reflections [20]. All data were cor-
rected for Lp effects by XCAD4 [21] and for absorption
by semi-empirical methods (c scan) [22]. The structure
was solved by Patterson method using DIRDIF-96 [23],
and refined anisotropically (non-hydrogen atoms) by
full-matrix least-square on F2 using SHELXL-97 [24]
program. The H atoms were calculated geometrically
and refined with a riding model. The program ORTEP-3
[25] was used for drawing the molecules. WINGX [26]
used to prepare material for publication. Experimental
data is given in Table 1.
40.8; H, 9.1%.) 1H NMR (C6D6, 500 MHz, d ppm): 1.03
3
(d, 12H, JHÃH
ꢃ
/
4.6 Hz, CH3), 1.21 (d, 9H, 2JPÃH
ꢃ
/
6.8
11.2
6.5 Hz, CH). 13C-{1H}
NMR (C6D6, 125 MHz, d ppm): 16.79 (d, JPÃC 13.1
Hz, P(CH3)3), 25.50 (s, CH3), 25.58 (s, CH2), 52.53 (d,
JPÃC
48.4 Hz, CH). 31P (C6D6, 202 MHz, d ppm):
45.97 (s, P(CH3)3), 69.31 (s, S2P). IR major bands and
tentative assignments 727 cmꢁ1 (n(CuÃS)), 804 cmꢁ1
S)).
3
2
Hz, PMe3), 2.13 (dd, 4H, JHÃH
ꢃ
/
5.9 Hz, JHÃP
ꢃ
/
3
Hz, CH2), 2.67 (m, 2H, JHÃH
ꢃ
/
ꢃ
/
Table 1
Crystal data and structure refinement
ꢃ
/
ꢁ
/
(1)
(2)
/
Empirical formula
Molecular weight
Temperature (K)
C
17H45CuP4S2
C44H48CuP3S2
797.39
180.0(1)
(n(PÄ
/
501.07
453(2)
Mo Ka
monoclinic
P21/a
Mass spectrum (m/z): [Mꢂ] 500 {((CH3)3P)3CuS2P-
[CH2CH(CH3)2]2}, base peak 57 {CH2CH(CH3)2}, 292
{(CH3)3PCuS2PCH2CH(CH3)2}, 234 {(CH3)3PCuS2P},
73 {CH2CH(CH3)2CH3}.
˚
l (A)
Mo Ka
monoclinic
¯
P1/
Crystal system
Space group
/
˚
a (A)
17.230(4)
17.263(4)
19.065(5)
90
12.152(4)
15.553(5)
12.662(4)
110.53(2)
63.56(1)
104.74(2)
1992(11)
2
˚
b (A)
˚
c (A)
2.3.2. Cu(S2PiBu2)×
/
(PPh3)2 (2)
a (8)
b (8)
g (8)
Volume (A )
Z
Dcalc (g cmꢁ3
m (mmꢁ1
F(000)
Crystal size (mm)
Dry CuCl (0.85 g, 8.6 mmol) was placed in a flask and
dry CH2Cl2 (30 ml) added. PPh3 (4.5 g, 17.2 mmol) was
added. This mixture was then stirred until it became
clear. Dried NaS2P(Bui)2 (2 g, 8.6 mmol) was added and
the mixture stirred for 2 h to ensure that the reaction
had occurred. The mixture was then filtered and the
filtrate concentrated. This was left to recrystallise over
several days at room temperature. Yield 5.2 g (75.9%),
m.p. 160 8C. (Anal. Found: C, 66.5; H, 6.1. Calc.: C,
101.95(3)
90
3
˚
5548(2)
8
1.200
)
1.329
0.804
)
1.169
2144
836
0.625ꢄ0.375ꢄ0.375
0.4ꢄ0.3ꢄ0.20
2u Range (8)
Observed reflections 8577
1.09ꢀ
/24.98
1.41ꢀ
7003
/
24.98
[I ꢀ2s(I)]
Refinement method
1
66.5; H, 6.2%). H NMR (CDCl3, 500 MHz, d ppm):
3
full-matrix least-
squares on F2
8557/0/481
full-matrix least-
squares on F2
7003/0/395
0.97 (d, 12H, JHÃH
ꢃ6.6 Hz, CH3), 1.91 (dd, 4H,
/
3JHÃH
CH), 7.23 (m, 4H), 7.32 (m, 2H), 7.41 (m, 4H). 13C-{1H}
NMR (CDCl3, 125 MHz, d ppm): 24.64 (d, JPÃC 8.9
Hz, CH3), 25.03 (d, JPÃC 3.3 Hz, CH2), 49.47 (d,
JPÃC 40.567 Hz, CH), 128.34 (d, JPÃC 8.6 Hz, CH),
129.27 (s, CH), 133.90 (s, CH), 134.05 (s, CH). 31P
NMR (CDCl3, 202 MHz, d ppm): ꢁ3.60 (s, PPh3),
75.18 (s, S2P). IR major bands and tentative assignments
604 cmꢁ1 (n(CuÃS)), 696 cmꢁ1 (n(PÃ
S)).
ꢃ
/
6.1 Hz, CH2), 2.11 (m, 2H, JHÃH
ꢃ/6.7 Hz,
3
Data/restraints/
parameters
Calculated weights
a
aꢃ0.0569, bꢃ0.00
0.0483
0.1473
aꢃ0.1308, bꢃ0.00
0.0637
0.1886
ꢃ
/
b
Final R
Final wR2
c
ꢃ
/
ꢃ
/
ꢃ
/
Goodness-of-fit on F2 1.019
1.081
a
wꢃ1[s2(Fo2)ꢂ(aP)2ꢂbP] where Pꢃ(Fo2ꢂ2Fc2)/3.
Rꢃa jjFojꢁjFcjj/a jFoj.
/
b
c
wR2ꢃ[a [w(Fo2ꢁFc2)2]/a [w(Fo2)2]]1/2
.
/
/

M.A. Malik et al. / Inorganica Chimica Acta 338 (2002) 245ꢀ
/
248
247
3. Results and discussion
Table 2
Selected bond lengths (A) and angles (8) for 1 and 2
˚
Both compounds 1 and 2 can be crystallised from
dichloromethane or pentane at room temperature and
are obtained as transparent plates. They are stable for
months under nitrogen at low temperature but turn into
white power on exposure to air.
Compound 1
Compound 2
Bond lengths
Cu(1)ÃP(1)
Cu(1)ÃP(3)
Cu(1)ÃP(2)
Cu(1)ÃS(2)
2.2476(13)
2.2622(13)
2.2721(14)
2.3777(14)
Cu(1)ÃP(2)
Cu(1)ÃP(3)
Cu(1)ÃS(1)
Cu(1)ÃS(2)
P(1)ÃS(1)
2.2842(13)
2.2852(12)
2.4527(14)
2.4584(14)
2.0062(15)
2.0119(15)
The molecular structure of compound 1 is based on a
monomer where copper is bonded to three phosphorus
˚
˚
P(2) 2.2721(14) A,
P(1)ÃS(2)
atoms (CuÃ
/
P(1) 2.2476(13) A, CuÃ
/
˚
Bond angles
CuÃP(3) 2.2622(13) A) and only one sulfur (CuÃ
/
/S(2)
˚
P(1)ÃCu(1)ÃP(3)
P(1)ÃCu(1)ÃP(2)
P(3)ÃCu(1)ÃP(2)
P(1)ÃCu(1)ÃS(2)
P(3)ÃCu(1)ÃS(2)
P(2)ÃCu(1)ÃS(2)
110.92(5)
109.51(5)
114.51(5)
125.01(5)
100.81(5)
95.45(5)
P(2)ÃCu(1)ÃP(3)
P(2)ÃCu(1)ÃS(1)
P(3)ÃCu(1)ÃS(1)
P(2)ÃCu(1)ÃS(2)
S(1)ÃCu(1)ÃS(2)
122.62(5)
106.57(4)
117.44(5)
113.54(5)
85.02(4)
2.3777(14) A) atom. The co-ordination geometry
around copper can be described as a distorted tetra-
hedron. Steric hindrance caused by the dangling sulfur
atom leads to a considerably larger angle P(1)Ã
/
Cu(1)Ã
/
S(2) 125.01(5)8 and smaller angle P(2)ÃCu(1)Ã
/
/
S(2)
95.45(5)8 around copper. To our knowledge this is the
only example in Cu(I) dithiophosphinate chemistry
where this particular mode of bonding exists. ORTEP
diagram with the atomic labelling scheme is shown in
Fig. 1. Selected bond lengths and angles are given in
Table 2.
The CuÃ
ably longer than those shown by other Cu(I) compounds
˚
S bond distance (2.3777(14) A) is consider-
/
e.g. Cu[S2P(OPri)2] (2.247ꢀ
/
2.289 A) [27] Cu[S2CNEt2)
2.290 A) [28], Cu[S2P(OEt)2]×phen (2.270ꢀ2.280
A) [29] and Cu8Cl2{S2P(OEt)2}6 (2.250ꢀ
but is close to those in [Cu{S2P(OEt)2}×bipy]2 (2.347ꢀ
˚
˚
(2.246ꢀ
/
/
/
˚
˚
2.280 A) [17]
/
/
/
˚
2.323 A) [15] and is shorter than those shown by other
Cu(II) compounds e.g. Cu(en)2{S2P(OEt)2}(SCN)
˚
˚
(3.09ꢀ
[30], Cu[S2P(OEt)2]×
[(Ph3P)Cu{S2P(OEt)2}]2 (2.455ꢀ
bond distance (2.248, 2.272, 2.262 A) is comparable to
/
2.99 A) [30], Cu(en)2{S2P(OEt)2}2 (3.04ꢀ2.90 A)
/
˚
2PPh3 (2.453ꢀ2.440 A) [13],
Fig. 2. The structure of Cu(S2PiBu2)×
(PPh3)2.
/
/
/
˚
/
2.357 A) [15]. CuÃ
/P
˚
˚
2.4584(14) A) and two phosphorus (CuÃ
CuÃ
/
P(2) 2.2842(13),
˚
2
those in Cu[S2P(OEt)2]×
[13], Cu(O2CCH3)×
B5H8)×2PPh3 (2.280, 2.260 A) [32].
/
2PPh3 (2.282, 2.264, 2.453 A)
˚
P(3) 2.2852(12) A) atoms and the co-ordination
/
˚
/
PPh3 (2.233, 2.240 A) [31], (Cu(h -
geometry is close to a tetrahedron. The dithiopho-
sphinate ligand chelates to the copper atom hence
behaves as a bidentate ligand and causes the largest
deviation from an ideal tetrahedron by a narrow bite
˚
/
Structure of compound 2 consists of a monomer as
shown in Fig. 2. Copper is four co-ordinate through
bonding to two sulfur (CuÃ
/
S(1) 2.4527(14), CuÃ
/
S(2)
angle (85.028) in contrast to compound 1 where it is
monodentate. CuÃ
close to those observed in Cu[S2P(OEt)2]×
˚
P (2.284, 2.285 A) bond distances are
/
/2PPh3 (2.282,
˚
˚
2.264, 2.453 A) [13], Cu(O2CCH3)×
[31], (Cu(h2-B5H8)×
Cu(S2PiBu2)×
bond distances (2.453, 2.458 A) are much longer than
/
PPh3 (2.233, 2.240 A)
˚
/2PPh3 (2.280, 2.260 A) [32] and
˚
/
(PMe3)3 (2.248, 2.272, 2.262 A). CuÃ
/
S
˚
those in Cu[S2P(OPri)2] (2.247ꢀ
/
2.289 A) [27] Cu[S2C-
2.290 A) [28], Cu[S2P(OEt)2]×phen
2.280 A) [29] and Cu8Cl2{S2P(OEt)2}6 (2.250ꢀ
˚
˚
NEt2) (2.246ꢀ
/
/
˚
(2.270ꢀ
/
/
˚
˚
2.280 A) [17],[Cu{S2P(OEt)2}×
/
bipy]2 (2.347ꢀ2.323 A)
/
[15]. These longer distances may be caused by the steric
effect of the bulkier group PPh3 as the bond distances
are very close to those observed in Cu[S2P(OEt)2]×
/2PPh3
˚
(2.453, 2.440 A) [13].
Fig. 1. The structure of Cu(S2PiBu2)×
(PMe3)3.
/

248
M.A. Malik et al. / Inorganica Chimica Acta 338 (2002) 245ꢀ248
/
[4] M. Mouche, J. Mermet, M. Romand, M. Charbonnier, Thin
Solid Films (1995) 1.
The most interesting difference in the two structures is
the behaviour of dithiophosphinate ligand. In com-
pound 1 it behaves as a monodentate whereas in
compound 2 it is bidentate. While there are quite a
few examples of dithiophosphinate ligands acting as
monodentate in Cu(I) complexes this is the only example
where a dithiophosphinate ligand is monodentate in a
Cu(I) complex.
[5] W. Lee Perry, A. Jain, T.T. Kodas, M.J. Hampden-Smith, Thin
Solid Films (1995) 7.
[6] N. Awaya, Y. Arita, Thin Solid Films (1995) 12.
[7] A.E. Kaloyeros, B. Zheng, I. Lou, J. Lau, J.W. Hellgeth, Thin
Solid Films (1995) 20.
[8] J. Wang, R.B. Little, W.G. Lai, G.L. Griffin, Thin Solid Films
(1995) 31.
[9] W.W. Lee, P.S. Locke, Thin Solid Films (1995) 39.
[10] J.A.T. Norman, D.A. Roberts, A.K. Hochberg, P. Smith, G.A.
Peterson, J.E. Parmeter, C.A. Apblett, T.R. Omstead, Thin Solid
Films (1995) 46.
4. Conclusion
[11] A. Jain, A.V. Gelatos, T.T. Kodas, M.J. Hampden, R. Marsh,
C.J. Mogab, Thin Solid Films (1995) 52.
Two new Cu(I) complexes Cu(S2PiBu2)×
/
(PMe3)3 1
[12] M.B. Naik, W.N. Gill, R.H. Wentorf, R.R. Reevs, Thin Solid
Films (1995) 60.
and Cu(S2PiBu2)×
/
(PPh3)2 2 have been synthesised and
[13] M. Drew, G. Forsyth, M. Husan, R. Hobson, D. Rice, J. Chem.
Soc., Dalton Trans. (1987) 1027.
characterised by NMR, IR, MS and elemental analysis.
The structure of both compounds have been determined
by X-ray single crystal method. Both structures consist
of monomers with four co-ordinate copper in a distorted
tetrahedron. Compound 1 is the only example in Cu(I)
complexes where a dithiophosphinate ligand is mono-
dentate.
[14] U. Tripathi, R. Bohra, G. Srivastana, R. Mehrotra, Polyhedron
11 (1992) 1187.
[15] Q. Chen, S. Lu, X. Huang, J. Huang, Jiegou Huaxue (J. Struct.
Chem.) 13 (1994) 102.
[16] Z. Huang, S. Lu, J. Huang, D. Wu, L. Huang, Jiegou Huaxue (J.
Struct. Chem.) 10 (1991) 213.
[17] D. Wu, J. Huang, Y. Lin, J. Huang, Sci. Sin. Ser. B (Engl. Ed.) 31
(1988) 800.
[18] S. Lawton, W. Rohrbaugh, G. Kokotailo, Inorg. Chem. 11 (1972)
612.
5. Supplementary material
[19] S. Du, X. Wu, Acta Crystallogr., C 50 (1994) 500.
[20] Enraf-Nonius CAD-4/PC Software, Version 1.5c Enraf-Nonius,
Delft, The Netherlands, 1992.
Crystallographic data for the structures reported in
this paper have been deposited with the Cambridge
Crystallographic Data Centre, CCDC Nos. 170358 and
[21] K. Harms, XCAD4, Program for data reduction, Philipps-
Universitat, Marburg, Germany, 1996.
¨
3170359 for compounds Cu(S2PiBu2)×
Cu(S2PiBu2)×
be obtained free of charge from The Director, CCDC,
12 Union Road, Cambridge, CB2 1EZ, UK (fax: ꢂ44-
/(PPh3)2 and
[22] A.C.T. North, D.C. Phillips, F.S. Mathews, Acta Crystallogr., A
42 (1968) 351.
/(PMe3). Copies of this information may
[23] P.T. Beurskens, G. Beurskens, W.P. Bosman, R. de Gelder, S.
Garcia-Granda, R.O. Gould, R. Israel, J.M.M. Smits, The
DIRDIF-96 Program System, Technical Report of the Crystal-
lography Laboratory, University of Nijmegen, Nijmegen, The
Netherlands, 1996.
/
1223-336-033; e-mail: deposit@ccdc.cam.ac.uk or www:
http://www.ccdc.cam.ac.uk).
[24] G.M. Sheldrick, SHELX-97, Program for solution, Refinement of
Crystal Structures, University of Gottingen, Gottingen, Germany,
¨
¨
1997.
[25] L.J. Farrugia, J. Appl. Crystallogr. 30 (1997) 565.
[26] L.J. Farrugia, WinGX* Windows Program for Crystal
Structure Analysis, University of Glasgow, Glasgow, 1998.
[27] S. Lawton, W. Rohrbaugh, G. Kokotailo, Inorg. Chem. 11 (1972)
612.
Acknowledgements
/A
C.B. and M.A.M. thank Sumitomo for grant. P.O.B
is the Sumitomo/STS visiting Professor of Materials
Chemistry at IC.
[28] R. Hesse, Ark. Kemi 20 (1963) 481.
[29] G. Dessy, V. Fares, A.A.G. Tomlinson, Proc. 4th Eur. Cryst.
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