Alkoxide accelerated 1,5-sigmatropy of alkyl, vinyl, aryl, and cyclopropyl groups
Abstract
The alkoxides (1a–e) undergo accelerated 1,5-shifts in hexamethylphosphoric triamide (HMPA) at 20 °C, and the alkoxides (6a–c) rearrange similarly in HMPA at 80–95 °C; the stereopecificity of the rearrangements and the exclusive formation of 2,2-disubstituted indanones (8) form (6) testify to the concerted nature of these shifts.