(2S,4S)-1-tert-butyl 2-(3-chloro-8-oxo-8,9,10,11-tetrahydro-5H-dibenzo[c,g]chromen-9-yl) 4-methylpyrrolidine-1,2-dicarboxylate 在
ammonium acetate 作用下,
以
5,5-dimethyl-1,3-cyclohexadiene 为溶剂,
以56%的产率得到(2S,4S)-tert-butyl 2-(9-chloro-4,5-dihydro-5H-naphtho[c,g]chromeno[8,9-d]imidazol-2-yl)-4-methylpyrrolidine-1-carboxylate