Azides siloxy

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]. 

Yamamoto has reported that ytterbium triisopropoxide, prepared in situ from Yb(OTf)3 and LiOPr in THF, can be used in a very mild, highly efficient, and widely applicable procedure for the azidolysis of epoxides. In every case except styrene oxide, products are derived from the attack of azide at the less hindered carbon atom. The method appears to be quite tolerant of functionality, leaving preexisting tosyl, acyl, and siloxy groups intact (e.g.,... 

Azidohydrins. Epoxides are converted to trans-siloxy azides by reaction with N3Si(CH3)3 (1.5 equiv.) and aluminum isopropoxide (1 equiv.) in CH2C12. The reaction involves selective attack of azide on the less-substituted carbon of the epoxide. 

Without additional reagents N-Silylcarboxylic acid amides from 1-siloxy-l-azides... 

Allylsilanes result from allyl sulphides which have siloxy subsdtuents with regio and stereochemically using allyl-lithium, from alkenyl Fischer carbene complexes with silanes through addition of Si-H to the carbene, and opdcally active y-silylallylamines result frnn a n-allylPd intermediate obtained from the carbonate using amines or azide, while allyldichlorosilane can be prepared by the direct method at 220 - 320 C as the main product. The protodesilyladon of allylsilanes provides a route to vinyl sulphones while silylmethyl allyl sulphones result from silylmethyl cuprates and sulphonylalka-1,2-dienes, and are used in the... 

Siloxy Isocyanates. Acyclic anhydrides react with TMSA in a manner similar to acid halides to give equal amounts of trimethylsilyl esters and isocyanates (eq 7). Similarly, cyclic anhydrides react with the azide to give < -trimethylsiloxycarbonyl alk(en)yl isocyanates (eq 8) which are further transformed into l,3-oxazine-2,6-dione derivatives (70-90%). ... 

Reactions with azidosilanes 1-Siloxy-l-azides from aldehydes... 

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