Results (A) Reaction of 1 with Piperidine. At Room Temperature with a Tenfold Excess of Piperidine. Under these conditions pyrroline 4a is the only product. It was characterized by'H NMR and CI mass spectroscopy, which showed an intense (M+ 1)+ peak. Pyrroliie 4a, like other related compounds such as 4, 5-bis (dialkylamino)-4, 5-dihydroimida~ oles,~ shows a very weak molecular peak in E1 mass spectroscopy. A nitro enamine structure, similar to ...
