Alkylidene-2H-pyrans by thermal electrocyclic ring closure of (2Z)-divinylallenals
作者:Angel R. de Lera、Alicia Torrado、José García Rey、Susana López
DOI:10.1016/s0040-4039(97)01746-2
日期:1997.10
Electrocyclic ring closure of (2Z)-divinylallenals 8 (including the retroretinal derivative 8a), afforded the corresponding alkylidene-2H-pyrans, under very mild conditions (25 °C, 48 h). Initially, an equilibrium between 8a and the kinetic product was observed, but this gradually reverted to the thermodynamically more stable .
(2Z)的电环环闭合-divinylallenals 8(包括复古视黄醛衍生物8a中),得到相应的亚烷基- 2 ħ -pyrans,非常温和的条件(25℃,48小时)下。最初,观察到8a与动力学产物之间的平衡,但是逐渐恢复到热力学上更稳定。