Enantioselective Multicomponent Condensation Reactions of Phenols, Aldehydes, and Boronates Catalyzed by Chiral Biphenols
作者:Keith S. Barbato、Yi Luan、Daniele Ramella、James S. Panek、Scott E. Schaus
DOI:10.1021/acs.orglett.5b02954
日期:2015.12.4
Chiral diols and biphenols catalyze the multicomponent condensation reaction of phenols, aldehydes, and alkenyl or aryl boronates. The condensation products are formed in good yields and enantioselectivities. The reaction proceeds via an initial Friedel–Crafts alkylation of the aldehyde and phenol to yield an ortho-quinone methide that undergoes an enantioselective boronate addition. A cyclization
手性二醇和联苯酚催化酚、醛和烯基或芳基硼酸酯的多组分缩合反应。缩合产物以良好的产率和对映选择性形成。该反应通过醛和苯酚的初始弗里德尔-克来福特烷基化进行,产生邻醌甲基化物,然后进行对映选择性硼酸酯加成。在探索提供手性 2,4-二芳基苯并二氢吡喃产物的反应范围时发现了环化途径,其核心是天然产物中发现的结构基序。