TY - JOUR
T1 - Synthesis, Structure, and Spectroscopy of [PPh4]2[(NC)Cu(μ-Se)2M(μ-Se)2Cu(CN)]·CH3CN and [PPh4]2[(NC)Cu(μ-Se)2MSe2] (M = Mo, W)
AU - Salm, Robert J.
AU - Ibers, James A.
PY - 1994/9/1
Y1 - 1994/9/1
N2 - [PPh4]2[MoSe4] and [PPh4]2[WSe4] react with 2 equiv of CuCN in CH3CN to afford [PPh4]2[(NC)Cu(μ-Se)2Mo(μ-Se)2Cu(CN)]·CH3CN (1) and [PPh4]2[(NC)Cu(μ-Se)2W(μ-Se)2Cu(CN)]·CH3CN (2), respectively. Compounds 1 and 2 are isostructural. Compound 1 crystallizes in the triclinic space group C1i-P1 with two formula units in a cell of dimensions a = 13.208(3) Å, b = 14.254(3) Å, c = 14.573(3) Å, α= 72.47(3)°, β = 74.09(3) °, and γ = 79.12(3)° at 113 K. Full anisotropic refinement of the structure on F02 led to a value of R(F) = 0.028 for those 7546 data having F02 >2σ(F02). The [(NC)Cu(μ-Se)2Mo(μ-Se)2Cu(CN)]2− anion of 1 comprises two CuCN fragments ligating the opposite edges of a tetrahedral [MoSe4]2− moiety; the Cu–Mo–Cu angle is 179.13(2)°;. Compounds 1 and 2 display an IR band at 2250 cm−1, which may be assigned to a CN stretching mode of the CH3CN solvate. Such a solvate molecule was found in the crystal structure of 1. The 77Se NMR spectra show a resonance at 1195 ppm for 1 and 920 ppm for 2. Addition of excess PMe2Ph to solutions of 1 and 2 results in the formation of [PPh4]2[(NC)Cu(μ-Se)2MoSe2] (3) and [PPh4]2[(NC)Cu(μ-Se)2WSe2] (4), respectively. Compounds 3 and 4 are isostructural. Compound 3 crystallizes in the monoclinic space group C62h-C2/c with four formula units in a cell of dimensions a = 11.254(2) Å, b = 20.153(4) Å, c = 20.191(4) Å, and β = 91.74(3)° at 113 K. Full anisotropic refinement of the structure on F02 led to a value of R(F) = 0.055 for those 3588 reflections having F02 > 2σ(F02)· The [(NC)Cu(μ-Se)2MoSe2]2− anion of 3, which has a crystallographically imposed 2-fold axis, comprises a CuCN fragment ligated across an edge of the tetrahedral [MoSe4]2− moiety. The 77Se NMR spectra show resonances at 1030 and 1820 ppm for compound 3 and at 782 and 1383 ppm for compound 4. The remaining NMR, IR, and electronic spectroscopic data of the four title compounds are also consistent with their solid-state structures.
AB - [PPh4]2[MoSe4] and [PPh4]2[WSe4] react with 2 equiv of CuCN in CH3CN to afford [PPh4]2[(NC)Cu(μ-Se)2Mo(μ-Se)2Cu(CN)]·CH3CN (1) and [PPh4]2[(NC)Cu(μ-Se)2W(μ-Se)2Cu(CN)]·CH3CN (2), respectively. Compounds 1 and 2 are isostructural. Compound 1 crystallizes in the triclinic space group C1i-P1 with two formula units in a cell of dimensions a = 13.208(3) Å, b = 14.254(3) Å, c = 14.573(3) Å, α= 72.47(3)°, β = 74.09(3) °, and γ = 79.12(3)° at 113 K. Full anisotropic refinement of the structure on F02 led to a value of R(F) = 0.028 for those 7546 data having F02 >2σ(F02). The [(NC)Cu(μ-Se)2Mo(μ-Se)2Cu(CN)]2− anion of 1 comprises two CuCN fragments ligating the opposite edges of a tetrahedral [MoSe4]2− moiety; the Cu–Mo–Cu angle is 179.13(2)°;. Compounds 1 and 2 display an IR band at 2250 cm−1, which may be assigned to a CN stretching mode of the CH3CN solvate. Such a solvate molecule was found in the crystal structure of 1. The 77Se NMR spectra show a resonance at 1195 ppm for 1 and 920 ppm for 2. Addition of excess PMe2Ph to solutions of 1 and 2 results in the formation of [PPh4]2[(NC)Cu(μ-Se)2MoSe2] (3) and [PPh4]2[(NC)Cu(μ-Se)2WSe2] (4), respectively. Compounds 3 and 4 are isostructural. Compound 3 crystallizes in the monoclinic space group C62h-C2/c with four formula units in a cell of dimensions a = 11.254(2) Å, b = 20.153(4) Å, c = 20.191(4) Å, and β = 91.74(3)° at 113 K. Full anisotropic refinement of the structure on F02 led to a value of R(F) = 0.055 for those 3588 reflections having F02 > 2σ(F02)· The [(NC)Cu(μ-Se)2MoSe2]2− anion of 3, which has a crystallographically imposed 2-fold axis, comprises a CuCN fragment ligated across an edge of the tetrahedral [MoSe4]2− moiety. The 77Se NMR spectra show resonances at 1030 and 1820 ppm for compound 3 and at 782 and 1383 ppm for compound 4. The remaining NMR, IR, and electronic spectroscopic data of the four title compounds are also consistent with their solid-state structures.
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U2 - 10.1021/ic00097a005
DO - 10.1021/ic00097a005
M3 - Article
AN - SCOPUS:0001428676
SN - 0020-1669
VL - 33
SP - 4216
EP - 4220
JO - Inorganic chemistry
JF - Inorganic chemistry
IS - 19
ER -