A dichotomy in the Friedel-Crafts reactions of lactones provides a convenient new route to 2-acylated pyrroles and tetrahydroindolones
作者:David C. Harrowven、Richard F. Dainty
DOI:10.1016/00404-0399(50)1328-f
日期:1995.9
In striking contrast to arenes, N-methylpyrrole undergoes Friedel-Crafts acylation with lactones. The reaction is most efficient with γ- and δ-lactones; ε-lactones proceed with poor overall conversion while β-lactones display poor selectivity. γ-Alkyl-γ-lactones readily yield 4,5,6,7-tetrahydroindol-7-ones through a sequence analogous to the Truce-Olson annulation.
与芳烃形成鲜明对比的是,N-甲基吡咯与内酯进行了Friedel-Crafts酰化反应。用γ-和δ-内酯进行反应最有效。ε-内酯的总转化率很低,而β-内酯的选择性很差。γ-烷基-γ-内酯通过类似于Truce-Olson环化的序列容易产生4,5,6,7-四氢吲哚-7-。