Novel intramolecular cyclization of N-acyliminium ions with allenylmethylsilane

ORGN 129

Moon Ho Chang,, Sang Hee Kim, Joo Hwan Cha, Ae Nim Pae,, Hun Yeong Koh, and Yong Seo Cho. Biochemicals Research Center, Korea Institute of Science and Technology, P.O. Box 131, Cheongryang, Seoul, 130-650, South Korea
Novel intramolecular cyclization of allenylsilane on a-acyliminium was developed in the presence of Lewis acid as TMSOTf or InCl3in CH2Cl2. Five-membered ring derivatives having dimethylenepyrrolidinyl moiety were afforded in the presence of InCl3 or TMSOTf  in 10~84% yields. Six-membered ring derivatives bearing dimethylenepiperidinyl moiety were obtained in the presence of TMSOTf in very high yields.