It has been found that N-alkylpyrrolidones do not undergo the Mannich reaction. Reaction is observed only following the introduction of an acetyl group at the pyrrolidone ring nitrogen (lla-c). However, replacement of the carbonyl group by thiocarbonyl increases C--H acidity in the 2-thiopyrroiidones, with the result that the 2-thiopyrrolidone (Ib) reacts with formaldehyde and secondary amines (dimethylamine
已经发现N-烷基
吡咯烷酮不发生曼尼希反应。仅在
吡咯烷酮环氮 (IIa-c) 处引入乙酰基后才观察到反应。然而,羰基被
硫代羰基取代会增加 2-
硫代
吡咯烷酮中的 C-H 酸度,结果 2-
硫代
吡咯烷酮 (Ib) 与
甲醛和仲胺(
二甲胺、吗啉、
哌啶和
吡咯烷)反应得到化合物(盖-g)。