Enzyme-Catalyzed Enantioselective and Regioselective Hydrolyses of (2<i>RS</i>,7<i>SR</i>)-2,7-Diacetoxybicyclo[2.2.1]heptane and (2<i>RS</i>,7<i>RS</i>)-2,7-Diacetoxybicydo[2.2.1]heptane
作者:Koichiro Naemura、Nobuo Takahashi、Shunsuke Tanaka、Michi Ueno、Hiroaki Chikamatsu
DOI:10.1246/bcsj.63.1010
日期:1990.4
and (+)-(2S,7R)-2-acetoxybicyclo[2.2.1]heptan-7-ol into (+)-(2R,7S)-bicyclo[2.2.1]heptane-2,7-diol (1) and (−)-(2S,7R)-bicyclo[2.2.1]heptane-2,7-diol (1), respectively, from which both enantiomers of 1 with ≥98% e.e. were readily obtained by further recrystallization. Similarly, (−)-(2R,7R)-2,7-diacetoxybicyclo[2.2.1]heptane (6) and (+)-(2S,7S)-2-acetoxybicyclo[2.2.1]heptan-7-ol (6) were converted into
(2RS,7SR)-2,7-二乙酰氧基双环 [2.2.1] 庚烷 (2) 及其 (2RS,7RS)-异构体 6 的酶催化水解具有区域特异性和对映体特异性,产生二乙酸酯和单乙酸酯旋光形式,位于二乙酸酯中甲桥上的乙酰氧基优先水解,得到单乙酸酯。用氢化铝锂处理将 (-)-2 和 (+)-(2S,7R)-2-乙酰氧基双环[2.2.1]庚烷-7-醇转化为 (+)-(2R,7S)-双环[2.2。 1]heptane-2,7-diol (1) 和 (-)-(2S,7R)-bicyclo[2.2.1]heptane-2,7-diol (1) 分别来自其中 1 的两种对映异构体 ≥通过进一步重结晶很容易获得 98% ee。类似地,(-)-(2R,7R)-2,7-二乙酰氧基双环[2.2.1]庚烷(6)和(+)-(2S,7S)-2-乙酰氧基双环[2.2.1]庚烷-7-醇(6)被转化为(+)-(2R,7R)-双环[2。2