2-Trimethylsiloxy azides

Trimethylsiloxy azides. This system reacts rapidly with epoxides to give trimethylsiloxy azides by attack at the less-substituted carbon. The products are precursors to azidohydrins and (3-amino alcohols. 

Functionalized epoxides are regioselectively opened by use of trimethylsilyl azide-Al(OPr )3 giving 2-trimethylsiloxy azides by attack on the less substituted carbon (Sch. 15) this provides a promising way for the preparation of /3-amino aleohols [35]. The functional groups acetoxy, methoxy, phenoxy, tert-butoxy, p-toluenesulfonyloxy, phthalimido, chloro, and bromo were unaffected in this reaction. 

If chloral (239) is treated with dimethyl-TMS-amine (187), l-(trimethylsiloxy)-l-dimethylamino-2,2,2-trichloro-ethane (244) is obtained via -elimination this yields dimethylformamide (245)l64 TMS-azide (14) forms with n-butanal (240) 1-azido-1-trimethyl-siloxy-butane (24d)165 [see section El]. 

The reactions of TMSA (14) with aldehydes165 23° gives a-trimethylsiloxy-alkyl azides (246, 413-417) they are highly stable against hydrolysis and higher temperatures (Scheme 62). Thermolysis of the azides 246, 413-417 gives directly N-TMS-butyr- (246), valero- (413), capro- (414)-, isobutyr- (415)-, pival- (416) and trichloroacetamide (417), respectively. 

Treatment of (3-dicarbonyl compounds 461 with iodosylbenzene/TMSN3 in chloroform at reflux affords azides 462 in moderate to good yield (Scheme 3.183) [551]. Under similar conditions, 2-(trimethylsiloxy)furan (463) gives azidofuranone 464 as the main product [552]. 

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