Abstract This chapter discusses the reactions of 4-phosphorylated 5-hydroxypenta-2,3-dienoates with protected or unprotected hydroxy group involving 5-endo-trig cyclizations. Reactions with electrophiles produce mixtures of the 2,5-dihydro-1,2-oxaphosphole-5-carboxylates and the 5-phosphoryl-furan-2(5H)-ones by competitive electrophilic cyclization due to the neighboring phosphonate (phosphine oxide) and the carboxylate groups participation. 4-Phosphorylated 5-hydroxypenta-2,3-dienoates were smoothly converted into the corresponding 4-phosphoryl-2,5-dihydrofuran-2-carboxylates by using 5 mol% of a silver salt as a catalyst in the 5-endo-trig cycloisomerization reaction. Graphical Abstract

中文翻译：

---

三官能化的丙二烯。第三部分。4-磷酸化 5-hydroxypenta-2,3-dienoates 的亲电环化和环异构化：一种构建 2,5-dihydro-1,2-oxaphospholes、furan-2(5H)-ones 和 2,5-dihydrofurans 的简便合成方法

摘要 本章讨论了 4-磷酸化 5-羟基五-2,3-二烯酸酯与保护或未保护羟基的反应，涉及 5-endo-trig 环化。与亲电试剂的反应产生 2,5-dihydro-1,2-oxaphosphole-5-carboxylates 和 5-phosphoryl-furan-2(5H)-ones 的混合物，由于相邻的膦酸酯（氧化膦）和羧酸根基团的参与。通过在 5-endo-trig 中使用 5 mol% 的银盐作为催化剂，4-磷酸化的 5-羟基五-2,3-二烯酸酯被顺利转化为相应的 4-磷酰基-2,5-二氢呋喃-2-羧酸酯环异构化反应。图形概要