Construction of Successive Chiral Centers Adjacent to a Chiral Tetraalkylated Quaternary Center Using an Asymmetric Aldol Reaction
作者:Tomoyuki Esumi、Chihiro Yamamoto、Yuri Tsugawa、Masao Toyota、Yoshinori Asakawa、Yoshiyasu Fukuyama
DOI:10.1021/ol400556v
日期:2013.4.19
The aldol reaction of 2″ with a variety of different aldehydes gave the corresponding β-lactones 4 bearing successive asymmetric centers adjacent to a chiral tetraalkylated quaternary center or the (E)-alkenes 8. The use of electronically neutral or electron-deficient aldehydes led to 4 in excellent yields with high diastereoselectivities, whereas electron-rich aldehydes performed poorly and underwent
2寸与各种不同醛的醛缩反应使相应的β-内酯4带有连续的不对称中心,与手性四烷基季铵中心或(E)-烯烃8相邻。电子中性或电子不足的醛的使用导致4具有优异的非对映选择性高收率,而富电子醛表现不佳,并进行脱羧得到8。