Azides, reactions with silenes

The synthesis of siladihydrotriazoles 412a is easily achieved by the [2+3] cycloaddition reaction of azides RN3 with the silenes Me2Si=C(SiMe3)2 92 (equation 226). 

When deuteriated 92 is generated from irreversibly decomposing precursors, just the head-to-tail dimer [(D3C)2Si—C(SiMe3)2]2 is found97. An even faster reaction than the methyl migration is the reaction of the silene with silyl azides. Just one of the possible... 

A similar THF adduct has been isolated from the reaction of the stable silene 41 with tri-terf-butylsilyl azide, which presumably proceeds by a 3 + 2 cycloaddition and subsequent fragmentation (equation 130). At 60 °C, it slowly loses THF and is converted into the dimer of the silanimine115. 

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