Synthesis and unusual rearrangement of 2-organyl-4,4,6,6-tetramethyl-5-chloro-6λ5-sila-Δ2-dihydro-1,3,4λ4-oxadiazinium chlorides

The reactions of O-TMS derivatives of 1,1-dimethylhydrazides of trifluoroacetic and benzoic acids with Me₂Si(CHCl₂)Cl give 2-organyl-4,4,6,6-tetramethyl-5-chloro-6λ⁵-sila-Δ²-dihydro-1,3,4λ⁴-oxadiazinium chlorides which in CDCl₃ solution exhibit unexpected decomposition with the formation of Me₂SiCl₂, DMF and the corresponding organylcyanide.