PREPARATION AND NMR-STUDIES OF HEXACOORDINATED FLUOROSILICATES - NONDISSOCIATIVE FLUORINE SITE EXCHANGE WITHIN THE OCTAHEDRAL COMPLEXES IN SOLUTION

被引：42

作者：

BRELIERE, C ^{[1
]}

CARRE, F ^{[1
]}

CORRIU, RJP ^{[1
]}

DOUGLAS, WE ^{[1
]}

POIRIER, M ^{[1
]}

ROYO, G ^{[1
]}

MAN, MWC ^{[1
]}

机构：

[1] UNIV MONTPELLIER 2,HETEROCHIM & AMINO ACIDES LAB,CNRS,URA 1097,PL E BATAILLON,F-34095 MONTPELLIER 5,FRANCE

来源：

ORGANOMETALLICS | 1992年 / 11卷 / 04期

关键词：

D O I：

10.1021/om00040a032

中图分类号：

O61 [无机化学];

学科分类号：

070301 ; 081704 ;

摘要：

Stable 18-crown-6 potassium salts of hexacoordinated tetrafluorosilicates were readily prepared from pentacoordinated trifluorosilanes by reaction with KF/18-crown-6. It also proved possible to perform this transformation even in the absence of 18-crown-6. The crystal structure of the 18-crown-6-potassium salt of (8-(dimethylamino)naphthyl)tetrafluorosilicate was determined and the complex was found to exhibit slightly distorted octahedral geometry. Interestingly, the coordinative Si-N bond is shorter in this hexacoordinated complex (2.213 angstrom) than in the corresponding pentacoordinated one (2.318 angstrom). The results of solution NMR studies are consistent with the structure being octahedral. They indicate that intramolecular permutation of fluorine atoms occurs through a regular mechanism, such as the Bailar twist, without cleavage of either the Si-N or Si-F bonds. Similarly, a compound containing two hexacoordinated silicon atoms in the same molecule was prepared. Both silicons were found to be equivalent with fluorine site exchange occurring via a regular mechanism.

引用

页码：1586 / 1593

页数：8

共 56 条

[1] CRYSTAL-STRUCTURES OF 2,2'-BIPYRIDYLTETRAFLUOROSILICON(IV), 2,2'-BIPYRIDYLTETRAFLUOROGERMANIUM(IV), AND 2,2'-BIPYRIDYLTETRAFLUOROTIN(IV) [J].