Versatile [3 + 2] methylenecyclopentane annulations of unactivated and electron-rich olefins with [(trimethylsilyl)methylene]cyclopropanedicarboxylates
摘要:
[(Trimethylsilyl)methylene] cyclopropanedicarboxylates 8a-e are readily available from the cyclopropanation of the silylallenes 7a-e with dimethyl diazomalonate. The free-radical mediated methylenecyclopentane annulations of unactivated and electron-rich alkenes with 8a-e proceed in high yield. The product vinylsilanes are set up for diverse secondary conversions, making annulations with 8a-e highly versatile in the synthesis of cyclopentanes.