see text] The dimethyl(methylthio)sulfonium tetrafluoroborate induced cyclization of various bis(methylsulfanyl) carbonyl compounds is described. The reaction proceeds by methylthiolation of the thioacetal group to give a thionium ion which undergoes subsequent cyclization with the neighboring carbonyl group. This is followed by an elimination reaction to furnish the furan ring.
描述了四
氟硼酸二甲基(甲
硫基)ulf诱导的各种双(甲
硫基)羰基化合物的环化。该反应通过
硫代
缩醛基的甲基
硫醇化进行,得到
硫鎓离子,其随后与相邻的羰基环化。随后进行消除反应以提供
呋喃环。