Stereocontrol in organic synthesis using silicon-containing compounds. A synthesis of a (±)-carbacyclin analogue with the geometry of the exocyclic double bond controlled by the protodesilylation of an allylsilane
作者:Ian Fleming、Dick Higgins
DOI:10.1039/a804274h
日期:——
3.3.0]octan-2-one 13. Reduction gave the diastereoisomeric pair of allylic alcohols 14 and 15, both of which were converted into the allylsilane, 3-(1′-dimethylphenylsilyl-4′-methoxycarbonyl)butyl-7-tert-butyldimethylsilyloxy-8-cyanobicyclo[3.3.0]oct-2-ene 20. Protodesilylation of the allylsilane gave a high level of selectivity (>96∶4) in favour of the carbacyclin analogue, 5-(4′-methoxycarbonyl)
将已知的酮7-叔丁基二甲基甲硅烷氧基双环[3.3.0] oct-8-en-2-one 11分五步转化为3-(4'-甲氧基羰基丁烯)-7-叔丁基二甲基甲硅烷氧基-8-氰基双环[ 3.3.0]辛-2-酮13。还原得到非对映异构对的烯丙醇14和15,它们都被转化为烯丙基硅烷3-(1'-二甲基苯基甲硅烷基-4'-甲氧基羰基)丁基-7-叔丁基。 -丁基二甲基甲硅烷氧基-8-氰基双环[3.3.0]辛-2-烯20.烯丙基硅烷的原甲硅烷基化反应具有较高的选择性(> 96∶4),有利于碳环素类似物5-(4'-甲氧基羰基)丁烯具有与E的环外双键的-3-叔丁基二甲基甲硅烷氧基-2-氰基双环[3.3.0]辛烷22-配置。