The reactions of methyl 4,6-O-benzylidene-2-O-benzoyl- and -2-O-methyl-α-d-ribo-hexopyranosid-3-ulose with dichloromethyllithium gave the corresponding α-hydroxydichloromethyl derivatives in 75% and 87% yields, respectively. The structures of these products were determined by derivation into known compounds, respectively. A novel reaction of dichloromethyl derivatives with cesium acetate was found to give 3-α-hydroxyaldehyde or 3-α-acetoxyaldehyde derivative as a main product. SN2 inversion via spirochloroepoxide was suggested in this reaction by determining configuration of each product.
甲基4,6-O-亚苄基-2-O-苯甲酰基-和-2-O-甲基-α-d-
核糖-
吡喃糖苷-3-乌糖与二
氯甲基锂反应,得到相应的α-羟基二
氯甲基衍
生物,产率为75%收益率分别为 87%。这些产物的结构分别通过已知化合物的衍生来确定。发现二
氯甲基衍
生物与
乙酸铯的新反应可产生 3-α-羟基醛或 3-α-乙氧基醛衍
生物作为主要产物。通过确定每种产物的构型,建议在此反应中通过螺
氯环氧化物进行 SN2 反转。