An enantioselective synthesis of chromanylmethanol is described. An allylic alcohol moiety is, first, introduced on the aromatic ring through a Claisen transposition. Chirality is then introduced through asymmetric Sharpless epoxidation on the allylic alcohol moiety. Cyclization into the benzopyran ring is achieved by an intramolecular coupling between the tertiary alcoholic hydroxy and the hydroquinone moiety with an excellent retention of configuration.
介绍了一种对映体选择性合成
铬甲醇的方法。首先,通过克莱森转位反应在芳香环上引入一个烯丙基醇分子。然后通过烯丙基醇分子上的不对称 Sharpless 环氧化作用引入手性。通过
三级醇羟基和
对苯二酚分子间的分子内偶联,环化成
苯并呋喃环,并保持极佳的构型。