Authentic 3b (53%) and 3c (8%) were prepared from 2c, using, respectively, liquid ammonia6 and methylamine in ethyl ether (Scheme I). In the latter case, 1-methyl-2- iminopyrrolidine hydrochloride (4b, 8%) was also isolated. When 3b was autoclaved in ethanol, 4a was obtained in 50% yield, while similar treatment of 4a in ethanol with methylamine led to 2-methyliminopyrrolidine hydrochloride
