Alkyl 2-chloroacetoacetates undergo a complex reaction with dialkyl acetylenedicarboxylates in the presence of triphenylphosphine to produce a nearly 1:1 mixture of the cis/trans isomers of dialkyl 5-acetyl-2-oxo-3-(triphenylphosphoranylidene)tetrahydrofuran- 4,5-dicarboxylates in excellent yields.
2-
氯乙酰乙酸烷基酯在
三苯基膦的存在下与
乙炔基二
羧酸二烷基酯进行复杂反应,生成近乎1:1的5-乙酰基-2-氧-3-(三苯基正膦亚基)
四氢呋喃二烷基顺式/反式异构体混合物。 -二
羧酸盐具有优异的产率。