New synthetic methodology of heterocycles based on ubiquitous metal catalysts

铁和铋等普遍存在的金属因其π-和σ-酸性而被发现是非常活性的边界催化剂。基于这些特点，在温和的反应条件下，3-炔基酯的分子内碳氧基化、2-丙炔胺和1，3-二酮合成吡咯、N，O-烯基缩醛的环化反应、1，6-烯炔的环丙烷化反应和炔烃的分子内氢芳基化反应都取得了很好的效果，为合成许多有用的杂环化合物提供了新的方法。

Ubiquitous metals like iron and bismuth have been found to act as very reactive borderline catalysts due to their π- and σ-acidities. Based on these characteristics, intramolecular carbo-oxycarbonylation of 3-alkynyl esters, pyrrole synthesis from 2-propynylamines and 1,3-diketones, cyclization of alkenyl N,O-acetals, alkynylcyclopropanation of 1,6-enynes, and intramolecular hydroarylation of alkynes have been succeeded very effectively under mild conditions, which provide new synthetic methods for many useful heterocycles.