On the mechanism of base-induced rearrangements of epoxides to ketones: a formal synthesis of (S)-physoperuvine

Journal article

The enantioselective α-deprotonation-rearrangement of trans- and cis-5-silyloxycycloheptene oxides (trans-8 and cis-8) using organolithiums in the presence of (-)-sparteine 16 or (-)-α-isosparteine 17 to give predominantly 4-silyloxycycloheptanone [(R)-9 (up to 87% ee), a known intermediate in the synthesis of (S)-physoperuvine (10), and (S)-9 (up to 71% ee), respectively] is described; the results indicate an α-ring opening mechanism.

Authors: Hodgson, D; Robinson, L; Jones, M

• Publication status: Published
• Journal: TETRAHEDRON LETTERS
• Volume: 40
• Issue: 49
• Pages: 8637-8640
• Publication date: 1999-12-03
• DOI: 10.1016/S0040-4039(99)01810-9
• ISSN: 0040-4039
• Language: English
• Keywords: epoxide; organolithium; epoxidation; ketone