(R)-((2S,3S,4R)-2-Ethyl-5-oxo-4-phenylsulfanylmethyl-tetrahydro-furan-3-yl)-hydroxy-acetic acid methyl ester 在
camphor-10-sulfonic acid 作用下,
以
甲苯 为溶剂,
反应 36.0h,
以89%的产率得到(3α,3aα,4β,6aα)-(+/-)-4-Ethyldihydro-3-<(phenylthio)methyl>furo<3,4-b>furan-2,6(3H,4H)-dione