Asymmetric synthesis of (−)-denticulatins A and B via group-selective aldolization of a meso dialdehyde with a chiral N-propionylsultam
作者:Wolfgang Oppolzer、Jef De Brabander、Eric Walther、Gérald Bernardinelli
DOI:10.1016/0040-4039(95)00787-d
日期:1995.6
Aldolization of meso dialdehyde 3 with a borylenolate obtained from chiral N-propionylsultam 4 yields efficiently lactols 5 with simultaneous generation of five stereogenic centers.Dithioketalization/O-desilylation of 5 affords acyclic diol 9 which is converted into the marine polypropionates 1a and 1bvia the asymmetric alkylation of N-propionyltoluenesultam 11 and the aldol coupling 10 + 15 → 16.
的醛醇缩合内消旋二醛3与手性获得的borylenolate Ñ -propionylsultam 4倍的产率有效地乳醇5与同时产生的5立构centers.Dithioketalization / ø -desilylation的5得到无环二醇9被转换为海洋聚丙1A和1B通过在N-丙酰基甲苯磺酰胺11的不对称烷基化和羟醛偶联10 + 15→16。