Syntheses, Structures, and VT NMR Studies of Diselenophosphates of Group 14 Organometals. DFT Calculations for Gas-Phase Stability of Dinuclear Ions, [(Ph3M)2{
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- 作者：C. W. Liu ; Tarlok S. Lobana ; Jie-Liang Xiao ; Hong-Yuan Liu ; Ben-Jie Liaw ; Chiu-Ming Hung ; and Zhenyang Lin
- 刊名：Organometallics
- 出版年：2005
- 出版时间：August 1, 2005
- 年：2005
- 卷：24
- 期：16
- 页码：4072 - 4078
- 全文大小：223K
- 年卷期：v.24,no.16(August 1, 2005)
- ISSN：1520-6041
文摘
Equimolar reactions of group 14 compounds, (C6H5)3MCl with (NH4)[Se2P(OR)2], in diethylether yielded the first organometallic derivatives of diselenophosphates, viz., [Ph3M{
1-Se(Se)P(OR)2}] [M= Ge, R = Et, iPr, nPr (1-3); Sn, Et, iPr, nPr (4-6); Pb, Et, iPr, nPr (7-9)].The crystal structures of 1, 4, 6, and 7 showed that the geometry around a metal center foreach compound is distorted tetrahedral. The (1-Se) coordination mode with one pendant Seatom exhibited in these complexes is the new connective pattern for the diselenophosphates.31P and 77Se NMR spectral studies reveal that whereas germanium compounds do not showlability of Ge-Se bonds, the Sn and Pb compounds do exhibit lability of Sn-Se and Pb-Sebonds, which involve exchange of the coordinated and pendant Se atoms at room temperature.This exchange process is slowed at low temperature and stopped at around 210 K. Theexchange energy (
G
) is calculated to be in the range of 38-46 kJ mol-1 for compounds4-9. Positive FAB-mass spectral data reveal that germanium compounds 1 and 3 have nearlyequal abundance of molecular ions [(Ph3M){
-Se, Se-P(OR)2}]+ and dinuclear cations [(Ph3M)2{- Se, Se-P(OR)2}]+; the same is not true for tin and lead compounds 4, 5, 7, and 8, whosedinuclear cations are several times intense over their molecular ions. The structures of thesedinuclear cations as well as their formation pathway have been studied by the densityfunctional theory calculations.
1-Se(Se)P(OR)2}] [M= Ge, R = Et, iPr, nPr (1-3); Sn, Et, iPr, nPr (4-6); Pb, Et, iPr, nPr (7-9)].The crystal structures of 1, 4, 6, and 7 showed that the geometry around a metal center foreach compound is distorted tetrahedral. The (1-Se) coordination mode with one pendant Seatom exhibited in these complexes is the new connective pattern for the diselenophosphates.31P and 77Se NMR spectral studies reveal that whereas germanium compounds do not showlability of Ge-Se bonds, the Sn and Pb compounds do exhibit lability of Sn-Se and Pb-Sebonds, which involve exchange of the coordinated and pendant Se atoms at room temperature.This exchange process is slowed at low temperature and stopped at around 210 K. Theexchange energy (G) is calculated to be in the range of 38-46 kJ mol-1 for compounds4-9. Positive FAB-mass spectral data reveal that germanium compounds 1 and 3 have nearlyequal abundance of molecular ions [(Ph3M){-Se, Se-P(OR)2}]+ and dinuclear cations [(Ph3M)2{- Se, Se-P(OR)2}]+; the same is not true for tin and lead compounds 4, 5, 7, and 8, whosedinuclear cations are several times intense over their molecular ions. The structures of thesedinuclear cations as well as their formation pathway have been studied by the densityfunctional theory calculations.© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号 地址：北京市海淀区学院路29号 邮编：100083 电话：办公室：(+86 10)66554848；文献借阅、咨询服务、科技查新：66554700 |