The Effects of Lewis Acid on the 1,3-Dipolar Cycloaddition Reaction of C-Arylaldonitrones with Alkenes.
作者:Tomio Shimizu、Masaya Ishizaki、Nobuo Nitada
DOI:10.1248/cpb.50.908
日期:——
The regio- and stereoselectivity of the 1,3-dipolar cycloaddition reactions of C-aryl-N-alkylaldonitrones (1a-e) with some alkenes were found to be affected significantly by the addition of Lewis acid. The rate of the reaction was also affected by adding the Lewis acid. In the reactions using allyl alcohol as a dipolarophile an addition of Lewis acid caused a remarkable acceleration of the reaction
发现路易斯酸对C-芳基-N-烷基醛酮(1a-e)与某些烯烃的1,3-偶极环加成反应的区域选择性和立体选择性具有显着影响。反应速度也受添加路易斯酸的影响。在使用烯丙醇作为双极性亲和剂的反应中,添加路易斯酸会显着加快反应速度,并极大地改变立体选择性。在使用丙烯酸乙酯作为双极性亲和剂的反应中,无论反应是在存在或不存在路易斯酸的条件下进行的,区域选择性都是相反的。即,异恶唑烷-5-羧酸盐主要在没有路易斯酸的情况下获得,尽管异恶唑烷-4-羧酸盐主要在路易斯酸的存在下获得。当C,N-二芳基醛酮(1k,1m,