α-α'-Dioxothione 3a acts as heterodiene undergoing 4+2 cycloaddition reactions with enol ethers with the regiospecific formation of 2,3-dihydro-1,4-oxathiines 5 in good yields. The reaction is very simple and quite general. Using this reaction the thiosugar derivative 5e has been also prepared.
α-α'-二氧杂
环丁烷3a用作异二烯,与烯醇醚进行4 + 2环加成反应,并以良好的产率形成2,3-二氢-1,4-氧杂亚砜5的区域特异性形成。该反应非常简单并且非常笼统。使用该反应,还制备了
硫糖衍
生物5e。