Naturally occurring hyacinthacines B-1 and B-2 have been prepared from a common, easily available, advanced intermediate. The approach features several highly stereoselective transformations: inter alia, a dichloroketene-enol ether [2 + 2] cycloaddition, a Bruylants alkylation, and an amino-nitrile alkylation-reduction.
Naturally occurring hyacinthacines B-1 and B-2 have been prepared from a common, easily available, advanced intermediate. The approach features several highly stereoselective transformations: inter alia, a dichloroketene-enol ether [2 + 2] cycloaddition, a Bruylants alkylation, and an amino-nitrile alkylation-reduction.
The first nonchiral-pool total synthesis of (+)-hyacinthacine B 1 has been achieved. The synthesis uses as key steps an efficient [2+2] cycloaddition of dichloroketene to a chiral enol ether, two diastereoselective Bruylants-like alkylations, and an effective double Tamao-Fleming oxidation.
(+)-hyacinthacine B 1 的第一个非手性池全合成已经实现。该合成使用二氯乙烯酮与手性烯醇醚的有效 [2+2] 环加成反应、两个非对映选择性的 Bruylants 类烷基化反应和有效的双 Tamao-Fleming 氧化作为关键步骤。