Thiazol-2-ylidene Catalysis in Intramolecular Crossed Aldehyde-Ketone Benzoin Reactions
作者:Dieter Enders、Oliver Niemeier
DOI:10.1055/s-2004-831306
日期:——
Intramolecular crossed aldehyde-ketone benzoin-type reactions catalyzed by nucleophilic carbenes, easily generated from commercially available thiazolium salts as precatalysts, are described. Five- and six-membered cyclicacyloins are obtained in moderate to good yields. Depending on the structure of the aldehyde-ketone substrate, an interchange of the alcohol and ketone function of the resulting acyloin
描述了由亲核卡宾催化的分子内交叉醛-酮安息香型反应,该反应很容易从作为预催化剂的市售噻唑鎓盐中产生。以中等至良好的产率获得五元和六元环酰基。取决于醛-酮底物的结构,所得到的丙烯酰基的醇和酮官能团的互换是可能的。由于竞争性分子间反应,简单的醛-酮不是好的底物。以联苯-2,2'-二甲醛为原料,通过温和的空气氧化将中间体丙烯酰转化为 9,10-菲醌。