Syntheses, Crystal Structures, and Density Functional Theory Calculations of the closo-[1-M(CO)3(4
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- 作者：Janette Campbell ; Hé ; lè ; ne P. A. Mercier ; Holger Franke ; David P. Santry ; David A. Dixon ; and Gary J. Schrobilgen
- 刊名：Inorganic Chemistry
- 出版年：2002
- 出版时间：January 14, 2002
- 年：2002
- 卷：41
- 期：1
- 页码：86 - 107
- 全文大小：375K
- 年卷期：v.41,no.1(January 14, 2002)
- ISSN：1520-510X
文摘
The closo-[1-M(CO)3(
4-E9)]4- (E = Sn, Pb; M = Mo, W) anions have been obtained by extracting the binary alloys KSn2.05and KPb2.26 in ethylenediamine (en) in the presence of 2,2,2-crypt or in liquid NH3 followed by reaction with M(CO)3·mes (M= Mo, W) or Cr(CO)3·tol in en or liquid NH3 solution. Crystallization of the molybdenum and tungsten salts was induced byvapor diffusion of tetrahydrofuran into the en solutions. The salts [2,2,2-crypt-K]4[1-M(CO)3(4-Sn9)]·en (M = Mo, W) crystallizein the triclinic system, space group P
, Z = 4, a = 16.187(3) Å, b = 25.832(4) Å, c = 29.855(5) Å, 
= 111.46(1)
, 
=102.84(2), 
= 92.87(2) at -95 C (M = Mo) and a = 17.018(3) Å, b = 27.057(5) Å, c = 28.298(6) Å, = 66.42(3), = 76.72(3), = 87.27(3) at 20 C (M = W). The salts (CO)3M(en)2[2,2,2-crypt-K]4[1-M(CO)3(4-Pb9)]·2.5en (M = Mo, W)crystallize in the triclinic system, space group P, Z = 2, a = 16.319(3) Å, b = 17.078(3) Å, c = 24.827(5) Å, = 71.82(3), = 83.01(3), = 81.73(3) at -133 C (M = Mo) and a = 16.283(4) Å, b = 17.094(3) Å, c = 24.872(6) Å, = 71.62(2), = 82.91(2), = 81.35(2) at -153 C (M = W). The [1-M(CO)3(4-Sn9)]4- anions were also characterized in liquid NH3solution by 119Sn, 117Sn, and 95Mo NMR spectroscopy. Unlike their fluxional precursor, nido-Sn94-, NMR studies show that the[1-M(CO)3(4-Sn9)]4- anions are rigid on the NMR time scale. All possible inter- and intraenvironmental couplings, J(119,117Sn-119,117Sn), J(119,117Sn-183W), and one J(119,117Sn-95Mo) coupling, have been observed and assigned. Complete spin-spin couplingconstant assignments were achieved by detailed analyses and simulations of all spin multiplets that comprise the 119Sn and117Sn NMR spectra and that arise from natural abundance tin isotopomer distributions and from natural abundance 183W, in thecase of [1-W(CO)3(4-Sn9)]4-. Both the solid state and solution structures of the [1-M(CO)3(4-Sn9)]4- anions are based on acloso-bicapped square antiprismatic structure in which the transition metal occupies a cap position. The cluster structures areconsistent with Wade's rules for 22 (2n + 2) skeletal electron systems. Electron structure calculations at the density functionaltheory (DFT) level provide fully optimized geometries that are in agreement with the experimental structures. Complete assignmentof the NMR spectra was also aided by GIAO calculations. The calculated vibrational frequencies of the E94- and [1-M(CO)3(4-E9)]4- anions are also reported and are used to assign the solid-state vibrational spectra of the [1-M(CO)3(4-E9)]4- anions.
4-E9)]4- (E = Sn, Pb; M = Mo, W) anions have been obtained by extracting the binary alloys KSn2.05and KPb2.26 in ethylenediamine (en) in the presence of 2,2,2-crypt or in liquid NH3 followed by reaction with M(CO)3·mes (M= Mo, W) or Cr(CO)3·tol in en or liquid NH3 solution. Crystallization of the molybdenum and tungsten salts was induced byvapor diffusion of tetrahydrofuran into the en solutions. The salts [2,2,2-crypt-K]4[1-M(CO)3(4-Sn9)]·en (M = Mo, W) crystallizein the triclinic system, space group P, Z = 4, a = 16.187(3) Å, b = 25.832(4) Å, c = 29.855(5) Å, = 111.46(1), =102.84(2), = 92.87(2) at -95 C (M = Mo) and a = 17.018(3) Å, b = 27.057(5) Å, c = 28.298(6) Å, = 66.42(3), = 76.72(3), = 87.27(3) at 20 C (M = W). The salts (CO)3M(en)2[2,2,2-crypt-K]4[1-M(CO)3(4-Pb9)]·2.5en (M = Mo, W)crystallize in the triclinic system, space group P, Z = 2, a = 16.319(3) Å, b = 17.078(3) Å, c = 24.827(5) Å, = 71.82(3), = 83.01(3), = 81.73(3) at -133 C (M = Mo) and a = 16.283(4) Å, b = 17.094(3) Å, c = 24.872(6) Å, = 71.62(2), = 82.91(2), = 81.35(2) at -153 C (M = W). The [1-M(CO)3(4-Sn9)]4- anions were also characterized in liquid NH3solution by 119Sn, 117Sn, and 95Mo NMR spectroscopy. Unlike their fluxional precursor, nido-Sn94-, NMR studies show that the[1-M(CO)3(4-Sn9)]4- anions are rigid on the NMR time scale. All possible inter- and intraenvironmental couplings, J(119,117Sn-119,117Sn), J(119,117Sn-183W), and one J(119,117Sn-95Mo) coupling, have been observed and assigned. Complete spin-spin couplingconstant assignments were achieved by detailed analyses and simulations of all spin multiplets that comprise the 119Sn and117Sn NMR spectra and that arise from natural abundance tin isotopomer distributions and from natural abundance 183W, in thecase of [1-W(CO)3(4-Sn9)]4-. Both the solid state and solution structures of the [1-M(CO)3(4-Sn9)]4- anions are based on acloso-bicapped square antiprismatic structure in which the transition metal occupies a cap position. The cluster structures areconsistent with Wade's rules for 22 (2n + 2) skeletal electron systems. Electron structure calculations at the density functionaltheory (DFT) level provide fully optimized geometries that are in agreement with the experimental structures. Complete assignmentof the NMR spectra was also aided by GIAO calculations. The calculated vibrational frequencies of the E94- and [1-M(CO)3(4-E9)]4- anions are also reported and are used to assign the solid-state vibrational spectra of the [1-M(CO)3(4-E9)]4- anions.