Alkenes from cyclic sulfates and thionocarbonates of 1,2-diols via tellurium chemistry
作者:Bin Chao、Kenneth C. McNulty、Donald C. Dittmer
DOI:10.1016/0040-4039(95)01532-m
日期:1995.10
stereospecific, e.g. meso-2,3-diphenylethane 2,3-diol → cis-stilbene; d,l-2,3-diphenylethane-2,3-diol → trans-stilbene. Unsaturated mannose and ribose derivatives have been obtained, and diethyl (-)-tartrate gives diethyl fumarate. The reaction may be performed with 0.1 equiv or less of elemental tellurium in the presence of a stoichiometric amount of reducing agent. Reaction of telluride ion with cyclic thionocarbonates
通过元素还原原位生成的碲化物离子处理1,2-二醇环状硫酸盐(1,3,2-二氧杂硫杂环戊烷2,2-二氧化物),在温和的条件下(10分钟至2小时)快速产生烯烃。 0°C至室温)。该反应是立体特异性的,例如内消旋-2,3-二苯基乙烷2,3-二醇→顺式-sti; d,l -2,3-二苯基乙烷-2,3-二醇→反式-sti。已经获得了不饱和的甘露糖和核糖衍生物,(-)-酒石酸二乙酯得到了富马酸二乙酯。该反应可以在化学计量的还原剂存在下用0.1当量或更少的元素碲进行。碲化物离子与内消旋的环状硫代碳酸酯(1,3-二氧戊环-2-硫酮)反应-和d,1-,1,2-二苯基乙烷-1,2-二醇分别产生顺式-和反式-二苯乙烯。