Silacyclopropene: Generation by High-Vacuum Flash Pyrolysis and Malrix-Spectroscopic Identification

摘要

In 1961 Voi'pin et ai reported the synthesis of a compound with a silacyciopropene structure. However, it was shown soon afterwards that the structure assignment was incorrect and that the isolated product was a 1,4-disilacyclohexa-2,5-diene. This resulted in renewed attempts to produce silacycloprope-nes. These proved unsuccessful until 1976, when Gaspar et al. succeeded for the first time in preparing a substituted silacyclo-propene. Shortly afterwards the synthesis of furthei silacyclo propenes was reported. At that time two methods were available for the synthesis of this class of substances. One en-abied the formation of silacydopropenes by the addition of substituied silanediyls (silylenes) to disubstituted alkynes, and the other by the photolysis of alkynylclisilanes. Recently silacyclopropene chemistry has experienced an upswing: the first stable silacydopropenes monosubstituted at the double bond were prepared. Sander et al, carne close to the synthesis of the unsubstituted parent compoundwith the generation of 1,1-dirnethylsilacyclopropene by the photolysis of a bis(di-azomethyl)silane. The first silacyciopropene not substituted at the double bond was obtained in this way.