Synthesis and crystal structures of [CuCl2(μ-NSPh3)]2 and [CuCl2(Ph3SN)2]: Novel copper complexes bearing organic λ6-sulfanenitrile as ligand

Article abstract of DOI:10.1246/cl.2002.1000

Dinuclear complex [CuCl₂(μ-NSPh₃)]₂ (2) and mononuclear complex [CuCl₂(Ph₃SN)₂] (3) were obtained concurrently by a reaction of CuCl₂ with triphenyl-λ⁶-sulfanenitrile (1) in acetonitrile. They were characterized by elemental analysis, IR and NMR spectroscopy, and their molecular structures were determined by X-ray crystallographic analysis.

Full text of DOI:10.1246/cl.2002.1000

1000
Chemistry Letters 2002
Synthesis and Crystal Structures of [CuCl2(ꢀ-NSPh3)]2 and [CuCl2(Ph3SN)2]:
Novel Copper Complexes Bearing Organic ꢁ6-Sulfanenitrile as Ligand
Toshiaki Yoshimura,ꢀ Takayoshi Fujii, and Huagang Dai
Department of Material Systems Engineering and Life Science, Faculty of Engineering, Toyama University, Gofuku, Toyama 930-8555
(Received June 27, 2002; CL-020538)
Dinuclear complex [CuCl2(ꢀ-NSPh3)]2
(2) and
mononuclear complex [CuCl2(Ph3SN)2] (3) were obtained
concurrently by a reaction of CuCl2 with triphenyl-ꢁ6-sulfaneni-
trile (1) in acetonitrile. They were characterized by elemental
analysis, IR and NMR spectroscopy, and their molecular
structures were determined by X-ray crystallographic analysis.
Thiazyl fluoride (FSꢁN) and thiazyl trifluoride (F3SꢁN)
were first prepared in inorganic field by Glemser and Mews et al.,
and their metal coordination chemistry has been investigated in
recent years.1;2 In 1992, we reported the synthesis of organic ꢁ6-
sulfanenitrile, fluorodiphenyl-ꢁ6-sulfanenitrile (FPh2SꢁN).3 We
have subsequently succeeded in transforming fluoro-ꢁ6-sulfane-
nitrile to the various substituted ꢁ6-sulfanenitriles.4 Their
structures have been elucidated by X-ray crystallographic
analysis and the reactivities have been clarified.4{6 Sulfanenitriles
have a nitrile-like nitrogen atom which is expected to coordinate
toward metals. However there has been no report on the
coordination chemistry of organic sulfanenitriles. As a part of
continuing research on ꢁ6-sulfanenitrile, we have recently begun
to study the coordination chemistry for sulfanenitrile as ligand
toward transition metal center.
Scheme 1.
spectroscopy of 2 exhibits reasonably sharp, isotropically shifted
signals.8;9 This is an evidence of the presence of two
paramagnetic copper centers in 2, and this is also associated with
the speculation from the results of elemental analysis. All
speculations about 2 were confirmed by X-ray crystallographic
analysis.
The single crystals of 2 suitable for X-ray analysis were
obtained finally by diffusing diethyl ether to DMF solution of 2.
The X-ray analysis clearly reveals that it is centrosymmetric
dinuclear complex containing two bridging sulfanenitrile groups
(Figure 1).10 Each terminal copper atom of the cyclic Cu2N2
square exhibits a tetrahedral coordination with two chlorine
atoms and two sulfanenitrile ligands bound by their nitrogen
Triphenyl-ꢁ6-sulfanenitrile (Ph3SꢁN) (1) was prepared by
the reaction of fluorodiphenyl-ꢁ6-sulfanenitrile with phenyl-
lithium, and its molecular structure was revealed by X-ray
crystallographic analysis.4c Compound 1 is thermally much more
stable than other sulfanenitriles, and SꢁN group has a stronger
electron-donating nature,4c,7 which is easier to incorporate into
transition metal compounds as ligand. Therefore in the research
project, reactions of 1 with transition metal salts were tried to
prepare its metal complexes. We are stimulated to investigate the
coordination chemistry of 1 as ligand toward copper center in the
first place.
ꢀ
donors with Cu–N bonds of 2.016 A in length. The nitrogen atom
of sulfanenitrile is fixed in a bridging position, and the S–N bond
ꢀ
(1.505 A) of 2 is considerably longer than in the free ligand
4c
ꢀ
(1.462 A), other bond lengths and angles of sulfanenitrile as
Addition of 1.2 equimolar amount of 1 to CuCl2 in anhydrous
acetonitrile at ambient temperature gave dark brown precipitates
of 2 in 79% yield which was redissolve upon further treatment of
another molar amount of 1 in acetonitrile. After removal of the
precipitates and the solvent, recrystallization of the residue from
acetonitrile–diethyl ether gave brown crystals 3 in 44% yield.
Addition of CuCl2 to the solution of 3 in acetonitrile afforded
again 2, and therefore the compounds 2 and 3 can be
interconverted to one anther (Scheme 1).
ꢀ
Figure 1. ORTEP drawings of 2. Selected bond lengths (A)
The data from elemental analysis shows that the obtained
complex 2 is a 1 : 1 complex of CuCl2 and 1.8 The IR spectral data
for 2 is also associated with its molecular structure.8 As the SN
stretching band is present at 1118 cmꢂ1, which is lower than that
of 1 in the free ligand (ꢂSN ¼ 1267 cmꢂ1),4c it is suggested that
there is a longer SN bond in 2. The other signals are slightly
shifted with respect to those shown in the free ligand. 1H NMR
and angles (ꢃ): S1–N1 1.505(4), S1–C1 1.790(4), S1–C2
1.802(5), S1–C3 1.795(4), Cl1–Cu1 2.205(1), Cl2–Cu1
2.229(1), N1–Cu1 2.016(3), N1–S1–C1 116.9(2), N1–S1–
C2 113.2(2), N1–S1–C3 111.8(2), C1–S1–C2 104.5(2), C2–
S1–C3 103.5(2), C3–S1–C1 105.6(2), Cu1–N1–S1 131.2(2),
Cl1–Cu1–Cl2 102.6(5), N1–Cu1–N1ꢀ 83.3(1), Cu1–N1–
Cu1ꢀ 96.7(1).
Copyright Ó 2002 The Chemical Society of Japan

Chemistry Letters 2002
1001
ligand correspond closely to those of the free state. As far as we
are aware, this is the first instance of organic ꢁ6-sulfanenitrile as
ligand in coordination chemistry.
1992, 2213. c) T. Yoshimura, K. Hamada, M. Imado, K.
Hamata, K. Tomoda, T. Fujii, H. Morita, C. Shimasaki, S. Ono,
E. Tsukurimichi, N. Furukawa, and T. Kimura, J. Org. Chem.,
62, 3802 (1997). d) T. Yoshimura, M. Ohkubo, T. Fujii, H. Kita,
Y. Wakai, S. Ono, H. Morita, C. Shimasaki, and E. Horn, Bull.
Chem. Soc. Jpn., 71, 1629 (1998). e) T. Yoshimura, T. Fujii, S.
Murotani, S. Miyoshi, T. Fujimori, M. Ohkubo, S. Ono, and H.
Morita, J. Organomet. Chem., 611, 272 (2000). f) T. Fujii, A.
Itoh, K. Hamata, and T. Yoshimura, Tetrahedron Lett., 42, 5041
(2001). g) T. Fujii, T. Suzuki, T. Sato, E. Horn, and T.
Yoshimura, Tetrahedron Lett., 42, 6151 (2001).
Complex 3 obtained as minor product in the reaction of 1 and
CuCl2 was also investigated. The data from elemental analysis
shows that 3 is a product with a CuCl2: 1 molar ratio of 1 : 2.8
Complex 3 exhibits a strong IR absorption at 1225 cmꢂ1
1
attributable to the SN stretching band.8 The H NMR spectro-
scopy of 3 does not show any signals for paramagnetic reason.
The structure of 3 was determined by X-ray crystallographic
analysis, which revealed a pseudo-tetrahedral coordination
geometry of the copper atom (Figure 2).10 The copper atom
which lies on symmetry center is coordinated by two chlorine
atoms and two sulfanenitriles via their nitrogen donors with
5
6
a) E. Horn, T. Dong, T. Fujii, T. Yoshimura, and C. Shimasaki,
Z. Kristallogr.-New Cryst. Struct., 215, 356 (2000). b) T. Fujii,
T. Fujimori, S. Miyoshi, S. Murotani, M. Ohkubo, and T.
Yoshimura, Heteroat. Chem., 12, 263 (2001).
ꢀ
shorter Cu–N bonds (1.969 A) than in 2. The S–N bond (1.464 A)
ꢀ
of 3 is approximately considered not to be changed contrast to in
4c
a) T. Yoshimura, T. Dong, T. Fujii, M. Ohkubo, M. Sakuta, Y.
Wakai, S. Ono, H. Morita, and C. Shimazaki, Bull. Chem. Soc.
Jpn., 73, 957 (2000). b) T. Dong, T. Fujii, S. Murotani, H. Dai, S.
Ono, H. Morita, C. Shimazaki, and T. Yoshimura, Bull. Chem.
Soc. Jpn., 74, 945 (2001).
ꢀ
the free ligand (1.462 A), and is considerably shorter than in 2
ꢀ
(1.505 A).
7
8
T. Yoshimura, T. Fujii, K. Hamata, M. Imado, H. Morita, S.
Ono, and E. Horn, Chem. Lett., 1998, 1013.
For 2: dark brown crystals, mp 228–230 ꢃC, 1H NMR
(400 MHz, DMF-d7): ꢃ 7.65 (bs, 12H), 9.83 (bs, 18H); IR
(KBr): ꢂSN ¼ 1118 cmꢂ1; Anal. Calcd for C36H30Cl4Cu2N2S2:
C, 52.50; H, 3.67; N, 3.40%. Found: C, 52.66; H, 3.78; N,
3.54%. For 3: brown crystals, mp 214–216 ꢃC, IR (KBr):
ꢂSN ¼ 1225 cmꢂ1; Anal. Calcd for C36H30Cl2Cu1N2S2: C,
62.74; H, 4.39; N, 4.06%. Found: C, 62.99; H, 4.46; N, 4.16%.
1H NMR Spectroscopy of Binuclear Copper (II) Complex; see:
a) M. Navarro, E. J. Cisneros-Fajardo, T. Lehmann, R. A.
Sanchez-Delgado, R. Atencio, P. Silva, R. Lira, and J. A.
Urbina, Inorg. Chem., 40, 6879 (2001). b) J. H. Satcher and A. L.
Balch, Inorg. Chem., 34, 3371 (1995). c) R. C. Holz, J. M. Brink,
F. T. Gobena, and C. J. O’Connor, Inorg. Chem., 33, 6086
(1994). d) N. Kitajima, K. Fujisawa, C. Fujimoto, Y. Moro-oka,
S. Hashimoto, T. Kitagawa, K. Toriumi, K. Tatsumi, and A.
Nakamura, J. Am. Chem. Soc., 114, 1277 (1992).
9
ꢀ
Figure 2. ORTEP drawings of 3. Selected bond lengths (A)
and angles (ꢃ): S1–N1 1.464(4), S1–C1 1.811(5), S1–C2
1.805(5), S1–C3 1.802(5), Cl1–Cu1 2.249(2), N1–Cu1
1.969(4), N1–S1–C1 117.0(2), N1–S1–C2 111.1(2), N1–S1–
C3 117.4(2), C1–S1–C2 102.5(2), C2–S1–C3 102.3(2), C3–
S1–C1 104.7(2), Cu1–N1–S1 131.9(2), N1–Cu1–Cl1
102.7(1), N1–Cu1–N1ꢀ 96.9(3), Cl1–Cu1–Cl1ꢀ 105.2(1).
10 Crystallographic data for 2: C36H30Cl4Cu2N2S2, Mr ¼ 823:67,
ꢀ
orthorhombic, a ¼ 19:347ð3Þ, b ¼ 16:712ð3Þ, c ¼ 10:740ð2Þ A,
ꢀ 3
V ¼ 3472ð1Þ A , T ¼ 296 K, space group Pbca (No. 61),
Z ¼ 4, ꢀðMo KꢄÞ ¼ 16:82 cmꢂ1, 5597 reflections were col-
lected, 5036 were unique; RðI > 3ꢅðIÞÞ ¼ 0:043, Rw ¼ 0:054
for 2524 reflections and 208 parameters. Crystallographic data
for 3: C36H30Cl2Cu1N2S2, Mr ¼ 689:22, orthorhombic, a ¼
Further investigations on the coordination chemistry of 1 and
CuCl2 are in progress in our laboratory.
ꢀ
ꢀ 3
15:679ð2Þ, b ¼ 12:210ð2Þ, c ¼ 17:155ð2Þ A, V ¼ 3284ð1Þ A ,
T ¼ 296 K, space group Aba2 (No. 41), Z ¼ 4,
ꢀðMo KꢄÞ ¼ 9:83 cmꢂ1, 2655 reflections were collected,
2465 were unique; RðI > 3ꢅðIÞÞ ¼ 0:034, Rw ¼ 0:048 for
1727 reflections and 194 parameters. Crystallographic data
reported in this paper have been deposited with Cambridge
Crystallographic Data Centre as supplementary publication
no. CCDC-191400 (2) and 191401(3). Copies of the data can be
obtained free of charge on application to CCDC, 12 Union
Road, Cambridge, CB2 1EZ, UK (fax: (+44) 1223-336-033;
email: deposit@ccdc.cam.ac.uk). Instruction for depositing the
crystallographic data is available on the Web at http://
www.ccdc.cam.ac.uk/conts/depositing.html.
References and Notes
1
O. Glemser and R. Mews, Angew. Chem., Int. Ed. Engl., 19, 883
(1980) and references cited therein.
2
a) B. Buss, W. Clegg, G. Hartmann, P. G. Jones, R. Mews, M.
Noltemeyer, and G. M. Sheldrick, J. Chem. Soc., Dalton Trans.,
1981, 61. b) U. Behrens, R. Hoppenheit, W. Isenberg, E. Lork, J.
Petersen, and R. Mews, Z. Naturforsh., 49b, 238 (1994).
T. Yoshimura, H. Kita, K. Takeuchi, E. Takata, K. Hasegawa,
C. Shimasaki, and E. Tsukurimichi, Chem. Lett., 1992, 1433.
a) T. Yoshimura, Rev. Heteroat. Chem., 22, 101 (2000) and
references cited therein. b) T. Yoshimura, E. Takata, T. Miyake,
C. Shimazaki, K. Hasegawa, and E. Tsukurimichi, Chem. Lett.,
3
4