(3R,3aR,3bS,4R,6aR,6bR)-2,3,4-Trihydroxy-3,3a,3b,4,6a,6b-hexahydro-2H-1-oxa-cyclobutadicyclopentene-4-carboxylic acid methyl ester 在
tris(dibenzylideneacetone)dipalladium(0) chloroform complex 、
碳酸二稀丙酯 作用下,
以
乙腈 为溶剂,
以49%的产率得到(3R,3aR,3bS,4R,6aR,6bR)-3,4-Dihydroxy-2-oxo-3,3a,3b,4,6a,6b-hexahydro-2H-1-oxa-cyclobutadicyclopentene-4-carboxylic acid methyl ester