Modified aluminium hydrides, their preparation and their use in reducing acetylnaphthalene derivatives
申请人:SUMITOMO CHEMICAL COMPANY, LIMITED
公开号:EP0035355A2
公开(公告)日:1981-09-09
A modified lithium aluminium hydride type reducing agent is useful for reducing organic compounds having a carbonyl group-(ketone group of aldehyde group) in their structure to the corresponding alcohols. It is obtained by reacting one equivalent of lithium aluminium hydride with one equivalent of an optically active N-substituted ephedrine of the formula,
(wherein R, is a Ci-C4 alkyl group or benzyl group and Ph is phenyl group)
and two equivalents of an N-substituted aniline of the formula,
(wherein R2 is a C1-C4 alkyl group or phenyl group, and Ph is phenyl group).
The reducing agent is particularly useful for reducing 2-acetyl-5, 8-dimethoxy-3, 4-dihydronaphthalene to the corresponding 2-(1'-hydroxy)ethyl compound, and, by selecting a particular modified aluminium hydride the unsymmetrical ketone can be reduced to selectively produce either an alcohol in which the asymmetric carbon atom bonded to the hydroxy group is in R-configuration or an alcohol in which said asymmetric carbon atom is in S-configuration.
一种改性氢化锂铝型还原剂可用于将结构中含有羰基(酮基或醛基)的有机化合物还原成相应的醇类。它是通过将 1 个当量的氢化锂铝与 1 个当量的光学活性 N-取代麻黄碱反应得到的,其化学式为
(其中 R 为 Ci-C4 烷基或苄基,Ph 为苯基)
和两个等量的 N-取代苯胺,其式为
(其中 R2 为 C1-C4 烷基或苯基,Ph 为苯基)。
还原剂特别适用于将 2-乙酰基-5,8-二甲氧基-3,4-二氢萘还原成相应的 2-(1'-羟基)乙基化合物,通过选择特定的改性氢化铝,可以将不对称酮还原,选择性地生成与羟基键合的不对称碳原子为 R 构型的醇或所述不对称碳原子为 S 构型的醇。