Affiliation:
1. Institut für Anorganische und Analytische Chemie der Technischen Universität, Hagenring 30, D-W-3300 Braunschweig
2. Department of Chemistry, The University of Durham, South Road, Durham DH 1 3 LE, England
Abstract
(CH3)3SiN(SO2CH3)2 (1), m. p. 69-70 °C, is obtained by metathesis of AgN(SO2CH3)2 with (CH3)3SiCl (improvement of a known procedure) or, more conveniently, by silylation of HN(SO2CH3)2 with [(CH3)3Si]2NH. The 1H, 13C and 29Si NMR solution spectra and the 29Si NMR solid-state spectrum suggest the constitution of 1 in solution (CDC13, CD2C12, CDCl2–CDCl2) to be an equilibrium mixture of the N-silylated form (CH3)3Si–N(SO2CH3)2 (I) and the O-silylated form (CH3)3Si–O–S(O)(CH3)=NSO2CH3 (II) in a molar ratio of 2:1 at room temperature, whereas in the known crystal structure of 1 only form I is present. The solid-state NMR experiment acted as a bridge between X-ray crystallography and solution-state NMR, enabling assignments of the resonances to be made with confidence to the tautomers. At room temperature, form II undergoes a rapid intramolecular 1.5-migration of silicon between oxygen centers of the two sulfonyl groups. As shown by kinetic measurements using 1H NMR spectroscopy, 1 is a highly reactive agent for silylating ketones in the presence of triethylamine. Hydroxy and thiol functions, even when sterically hindered, are silylated by 1 in uncatalyzed reactions. It is further shown that HN(SO2CH3)2 is an efficient catalyst for silylations with [(CH3)3Si]2NH.
Cited by
15 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献