摘要
本文比较了一系列Lewis酸在月桂烯与丙烯腈的Diels-Alder反应中的催化作用,催化剂的酸强度强烈影响月桂烯的转化率、柑菁腈的选择性及对位柑菁腈的区域选择性。这些选择性随反应温度的升高而下降,几乎不随反应时间而变化。利用UV,IR及1HNMR等分析研究了ZnCl2和AlCl3催化该反应的作用机理,证明反应是由丙烯腈的腈基与Lewis酸的金属离子发生配合作用,使得C=C双键极化,从而改变反应途径,提高反应速度和选择性。
The catalytic activities of a series of Lewis acids were compared in the DielsAlder reaction of myrcene with acrylonitrile. It was found that the acid strength affected the conversion of myrcene. the selectivity of myrac nitrile, and the regioselectivity of para myrac nitrile. All of these selcetivities decreased with increasing reaction temperature and almost unchanged with prolonging reaction time. The catalytic reaction mechanism of the Lewis acids with the acrylonitrile was investigated by UV.IR and HNMR methods. It was proved that the coordination of acrylonitrile with acid centres made the C=C bond polarized and increased their activities.
出处
《湖南师范大学自然科学学报》
CAS
1995年第3期50-54,共5页
Journal of Natural Science of Hunan Normal University
基金
湖南省自然科学基金
关键词
月桂希
丙烯腈
柑菁腈
催化
合成
myrcene
acrylonitrile: myrac nitrile
Lewis acid catalyst
Diels-Alderreaction
regioselctivity synthesis