derivative 8 which is a versatile synthon for the synthesis of valiolamine and its related compounds is described. Key steps in this preparation are a novel enol ether formation from spiro sugar ortho esters with AlMe3 and an intramolecular Aldol condensation of alkyl enol ethers catalyzed by ZnCl2 in THF-H2O. With these reactions, gluconolactone derivative 1 was efficiently converted into 8 in short
[反应:见正文]描述了一种短周期制备的环糖醇衍
生物8的方法,它是用于合成缬
氨酰胺及其相关化合物的通用合成子。该制备过程中的关键步骤是由螺旋
糖原酸酯与AlMe3形成新的烯醇醚,以及ZnCl2在THF-
H2O中催化的烷基烯醇醚的分子内Aldol缩合。通过这些反应,
葡糖酸内酯衍
生物1在短时间内有效地转化为8。