Study on the Reaction of Electron‐deficient Cyclopropane Derivatives with Amines

Reaction of electron deficient cyclopropane derivatives cis‐ 1‐methoxycarbonyl‐2‐aryl‐6, 6‐dimethyl‐5, 7‐dioxa‐spiro‐[2,5]‐4,8‐octadiones (1a‐d) (X = CH 3 , H, Cl, NO 2 ) with anilines (2a‐e) (Y = p ‐CH 3 , H, p ‐Br, p ‐NO 2 , o ‐CH 3 ) at room temperature gives N‐ aryl ‐trans, trans ‐α‐carboxyl‐β‐methoxycarbonyl‐γ‐aryl‐γ‐butyrolactams (3a‐p) in high yields with high stereoselectivity. For example, 1a (X= CH 3 ) reacts with ammonia 4 or benzyl amine 5 at room temperature to give inner ammonium salt 6 or 7 in the yield of 83% or 97% respectively. The reaction mechanisms for formation of the products are proposed.