The tertiary amino effect in heterocyclic synthesis : mechanistic and computational study of the formation of six-membered rings
作者:L.C. Groenen、W. Verboom、W.H.N. Nijhuis、D.N. Reinhoudt、G.J. Van Hummel、D. Feil
DOI:10.1016/s0040-4020(01)86166-4
日期:1988.1
The mechanism of the ring closure of [2-(1-pyrrolidinyl)phenylmethylene]-propanedinitrile (2a) to l,2,3,3a,4,5-hexahydropyrrolo[1,2-a]quinoline-4,4-dicarbonitrile (3a) has been studied by kinetic measurements using 1H-NMR spectroscopy. It could be shown that the rate-determining step consists of an intramolecular 1,5 hydrogen transfer, which is accompanied by charge separation within the- molecule
[2-(1-吡咯烷基)苯基亚甲基]-丙腈(2a)对1,2,3,3a,4,5-六氢吡咯并[1,2 - a ]喹啉-4,4-二腈的闭环机理(3a)已经通过使用1 H-NMR光谱的动力学测量来研究。可以表明,确定速率的步骤由分子内1,5氢转移组成,该转移伴随着分子内的电荷分离。计算出的2a(AM1)和实验(X射线)分子结构非常吻合。在基态几何结构中,最有可能发生1.5的氢转移。随后,前一个乙烯基的旋转和CC键的形成(导致六元环)也以立体化学定义的方式发生。