Silylation products of cyclic tri-aminal carbanions and their lithiation.
Silylation products of cyclic tri-aminal carbanions and their lithiation.
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环状三缩醛胺碳负离子的硅烷化产物及其锂化
DOI：
10.1039/c1dt10943j
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发表时间：
2012
影响因子：
4
通讯作者：
N. W. Mitzel
中科院分区：
文献类型：
--
作者：
C. Sicking;A. Mix;B. Neumann;H.-G. Stammler;N. W. Mitzel
The structure of 1,3,5-trimethyl-1,3,5-triaza-cyclohexane (TMTAC) was determined by single crystal X-ray diffraction and compared with earlier gas-phase data. It shows a preference for an aee-conformation in all phases. Lithiated TMTAC, [(RLi)2·(RH)] (1) (R = 2,4,6-trimethyl-2,4,6-triaza-cyclohex-1-yl), was reacted with Et3SiCl, Ph3SiCl and PhMe2SiCl to afford the substituted silanes Et3SiR (1), Ph3SiR (2) and PhMe2SiR (3) in moderate yields. They were characterised by NMR spectroscopy (1H, 13C, 29Si). 1 reacts with Me2SiCl2 and Ph2SiCl2 to give Me2SiR2 (5) and Ph2SiR2 (6) which were characterised by NMR spectroscopy. 5 was also identified by crystal structure determination. Analogous triple substitution could not be observed by employing trichlorosilanes. Quantumchemical calculations explain this by sterical overcrowding of the silicon atom. The reaction of 1 with SiCl4 did not yield fourfold substitution but a formal insertion product of SiCl2 into a C–N bond of the TMTAC ring (2,4,6-trimethyl-2,4,6-triaza-1,1-dichloro-1-sila-cycloheptane, 7) in very small quantities. It was identified by X-ray crystallography and shows an intramolecular Si⋯N dative bond. The reactions of (3) and (5) with n-butyl lithium afforded lithiation of the silicon bound methyl groups in both cases. The products, 8 and 9, were characterised by NMR spectroscopy (1H, 13C, 29Si), 8 was also characterised by X-ray crystallography.
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通过电子衍射分析气相中某些（二甲氨基）卤代硅烷的分子结构，通过低温 X 射线衍射分析单氯（二甲氨基）硅烷和二氯（二甲氨基）硅烷的晶体和分子结构
DOI：
--
发表时间：
1987
期刊：
影响因子：
--
作者：
David G. Anderson;A. Blake;S. Cradock;E. Ebsworth;D. Rankin;H. Robertson;A. J. Welch
通讯作者：
A. J. Welch
DOI：
10.1039/b205792c
发表时间：
2002-01-01
期刊：
JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS
影响因子：
--
作者：
Arnold, J;Knapp, V;Shafir, A
通讯作者：
Shafir, A
环状和无环缩醛胺直接金属化机制的变化。
影响因子：
--
作者：
Ina Kamps;Daniel Bojer;Stuart A. Hayes;R. J. Berger;B. Neumann;N. Mitzel
通讯作者：
N. Mitzel
通过 6Li、1H HOESY、133Cs、1H HOESY 和 MNDO 研究四氢呋喃溶液中超级碱的结构。
DOI：
--
发表时间：
1992
期刊：
影响因子：
--
作者：
W. Bauer;L. Lochmann
通讯作者：
L. Lochmann
影响因子：
15
作者：
R. O. Hutchins;L. Kopp;E. Eliel
通讯作者：
E. Eliel