A Facile Chemoenzymatic Route to Optically Active 4,5-Disubstituted-2E-hexenoate Derviatives. II.
作者:Hiroyuki AKITA、Isao UMEZAWA、Michika TAKANO、Takeshi OISHI
DOI:10.1248/cpb.41.680
日期:——
The reaction of (±) methyl 4, 5-trans-epoxy-(2E)-hexenoate (1) with nucleophile having heteroatoms in the presence of BF3·Et2 O gave the 4, 5-anti-5-hydroxy-4- and/or 2, 5-anti-5-hydroxy-2-substituted products. Among them, the (±)-4, 5-anti-5-hydroxy-4-thiophenoxy ester 12a was enantioselectively acetylated with acylating reagent in the presence of lipase "PL 266" from Alcaligenes sp. to provide the (4S, 5R)-5-acetoxy ester 12b and (4R, 5S)-12a quantitatively.
(±)-4,5-反式环氧-(2E)-己烯酸甲酯(1)在 BF3-Et2 O 的存在下与具有杂原子的亲核剂反应,得到 4,5-反式-5-羟基-4-和/或 2,5-反式-5-羟基-2-取代产物。其中,(±)-4,5-反-5-羟基-4-噻吩氧基酯 12a 在来自 Alcaligenes sp.的脂肪酶 "PL 266 "存在下,用酰化试剂进行对映选择性乙酰化,定量提供 (4S,5R)-5-乙酰氧基酯 12b 和 (4R,5S)-12a。