ChemInform Abstract: [3,3]‐Sigmatropic Rearrangement Step in the Gold‐Catalyzed Cyclization of Allyl‐(ortho‐alkinylphenyl)methyl Ethers.

Abstract

The reaction proceeds via a gold‐catalyzed cyclization step and [3,3]‐sigmatropic rearrangement with formal inversion of the allylic moiety.

Gold-Catalyzed Formal Hexadehydro-Diels–Alder/Carboalkoxylation Reaction Cascades

“…Crossover experiments were performed with substrates 1e and 1k, and 1 H NMR analysis of the crude reaction mixture showed no crossover cyclization products (Scheme 3b), suggesting that the 3,3-sigmatropic rearrangement step was concerted and did not involve the generation of an allylic cation. 13 Additional crossover experiments were performed with substrates 1a and 1t, from which both the 1,3-and 3,3-sigmatropic products were produced (Scheme 3c). However, HRMS analysis of the crude reaction mixture still showed no crossover cyclization products.…”