1972 年 92 巻 2 号 p. 204-206
Treatment of N-(2, 2-diethoxyethyl)-N-methyl-1, 3-bis(3, 4-dimethoxyphenyl)propylamine (X) with 6N hydrochloric acid at 20-25° resulted in the formation of an eight-membered ring to give homoisopavine (XI) in a good yield.