Peracid oxidation and photooxygenation reactions of silacyclopentadienes

Abstract

1-Methyl-1,2,3,4,5-pentaphenyl-1-silacyclopentadiene on treatment with perbenzoic acid afforded a mixture of products consisting of tetraphenylfuran, cis-dibenzoylstilbene, cis-dibenzoylstilbene epoxide, 2,5-dihydro-2,3,4,5-tetraphenylfuran, 1,2,3-triphenyl-1,3-propanedione, 1-methylphenylhydroxysilyl-1,2,3,4-tetraphenyl-1,3-butadiene and cis, cis-1,2,3,4-tetraphenyl-1,3-butadiene. Similarly, hexaphenylsilacyclopentadiene reacted with perbenzoic acid to give a mixture comprising tetraphenylfuran and cis-dibenzoylstilbene. Photooxygenation of 1-methyl-1-vinyl-2,3,4,5-tetraphenyl-1-silacyclopentadiene has been found to give a mixture of products including cis-dibenzoylstilbene, trans-dibenzoylstilbene and isodidesyl. Possible mechanistic pathways for these reactions have been suggested.