Stereochemistry of cyclic ether formation. Part I. Stereoselective intramolecular cyclisation of aliphatic disecondary 1,4-diols and their sulphonate esters to tetrahydrofurans
作者:M. Lj. Mihailović、S. Gojković、Ž. Čeković
DOI:10.1039/p19720002460
日期:——
Several methods of eliminative cyclisations of diastereoisomeric disecondary 1,4-diols and their 1,4-disulphonate esters, leading to the formation of tetrahydrofurans, have been studied, and it was found that they all proceed stereoselectively by SN2-type mechanisms, with inversion of configuration at one (1,4-diols) or both (1,4-disul-phonates) chiral centres, so that meso(i.e. erythro) 1,4-diols
研究了几种导致非对映异构的二仲1,4-二醇及其1,4-二磺酸酯消除环化的方法,这些方法导致形成四氢呋喃,并发现它们均通过S N 2型机理进行立体选择,在一个(1,4-二醇)或两个(1,4-二磺酸酯)手性中心构型反转,因此内消旋(即赤型)1,4-二醇和±(即苏式)1,4-二甲磺酸酯仅提供反式-2,5-二烷基四氢呋喃,而相应的非对映异构底物仅转化为顺式-2,5-二烷基四氢呋喃。