Michael acceptors to give anionic adducts, which undergo intramolecular substitution to give substituted tetrahydrofurans, pyrrolidines, and cyclopentanes. This has underlain a new method for the synthesis of these valuable ring systems. We have determined the acidity of the γ-halocarbanion precursors and have shown that the halogen atoms in the γ-position relative to the carbanion center exert a significant
短寿命的 γ-卤代碳负离子可以被醛、
亚胺和迈克尔受体等活性亲电子试剂捕获,生成阴离子加合物,然后进行分子内取代,生成取代的
四氢呋喃、
吡咯烷和
环戊烷。这为合成这些有价值的环系统提供了一种新方法。我们已经确定了 γ-卤代碳负离子前体的酸度,并表明相对于碳负离子中心的 γ 位的卤素原子对碳负离子产生显着的稳定作用。