입체선택적인 분자내 [2+2] 환화반응을 이용한 광학활성 Bicyclo[4.2.0]octanone의 합성

Stereoselective synthesis of the optically active bicyclo [4.2.0] octanone 5 was accomplished using intramolecular olefin-keteniminium salt[2+2]cycloaddition of the amide 4 as a key step. This important chiral synthon was prepared starting from readily available L-glutamic acid via an efficient 8-step sequence.