Gold(I)‐Catalyzed Reaction of 1‐(1‐Alkynyl)‐cyclopropyl Ketones with Vinyldiazo Ketones for Divergent Synthesis of Substituted Furanyl Heterocycles

Abstract Gold(I)‐catalyzed reactions between 1‐(1‐alkynyl) cyclopropyl ketones and vinyldiazo ketones to produce substituted [(furan‐3‐yl)ethyl]‐1 H ‐pyrazol‐5‐yl)methanones are described. In this reaction sequence, we postulate vinyldiazo ketones to undergo a thermal cyclization to produce pyrazole intermediates that attack gold‐containing all‐carbon 1,4‐carbon dipoles to afford the observed products. An atypical N(1)‐regioselectivity is also rationalized in this reaction model.