摘要
Pyrroles are cross-coupled with 1-acyl-2-bromoacetylenes on the surface of Al2O3 at room temperature under solvent-free conditions to afford 2-(acylethynyl)pyrroles with 100%regioselectivity and in good yields, thus representing the first example of a palladium-, copper-, base-, and solvent-free (芒芒芒green芒芒芒) ethynylation of pyrroles, which can be considered a formal 芒芒芒inverse Sonogashira coupling芒芒芒. Given the interest in functionalized pyrroles and acetylenes, this new facile and environmentally friendly cross-coupling should be of significant interest for the role of acylhaloacetylenes in pyrrole and acetylene chemistry.