ChemInform Abstract: A New Synthetic Method for Cyclopentanones via Formal (3 + 2) Cycloaddition Reaction.

Abstract

A New Synthetic Method for Cyclopentanones via Formal (3 + 2) Cycloaddition Reaction.-Alkenyl sulfides (II) react with AlCl3 or EtAlCl2 to give the corresponding 2-oxyallyl cations, which undergo a formal (3 + 2) cycloaddition with alkenes such as (I), (IV), and (VI) to give cyclopentanone derivatives. The reaction is highly regioselective to yield the sterically more hindered regioisomer. -(MASUYA, K.; DOMON, K.; TANINO, K.; KUWAJIMA, I.; Synlett (1996) 2, 157-158; Dep. Chem., Tokyo Inst. Technol., Meguro, Tokyo 152, Japan; EN)