described. Reactions of 1 with nitriles, isocyanates, and ketones give the corresponding 5-membered heterocycles in moderate yields, whereas those of 1 with acid chlorides afford α-chloroenones in moderate yields. Reactions of 1 with electron-rich and -deficient olefins such as vinyl ethers and allyl iodide give dihydrofurocoumarins as a single compound, whereas those of 3 with vinyl esters afford either angular
本文描述了
铑(II)催化的3-重氮-2,4-
氧化铬1-3与各种底物的反应。的反应1与腈类,
异氰酸酯,和酮,得到相应的5-元杂环在中等产率,而那些的1与酰
氯得到α-chloroenones在中等产率。的反应1与富电子和缺陷型的烯烃如
乙烯基醚和烯丙基
碘给予dihydrofurocoumarins作为单一化合物,而那些的3与
乙烯基酯得到任一角度dihydrofurocoumarin和线性产物或重排的产物,为异构体。此外,该新方法已应用于合成自叶绿素2分离的天然pterophyllin 2。翼状叶蕨。