Synthesis of Spirocyclic Isoindolones Using an Alkynyl aza-Prins/Oxidative halo-Nazarov Cyclization Sequence

Org Lett. 2021 Mar 5;23(5):1782-1786. doi: 10.1021/acs.orglett.1c00191. Epub 2021 Feb 16.

Abstract

In this report, we describe an alkynyl halo-aza-Prins cyclization of 3-hydroxyisoindolones to prepare aza-Prins products. These Prins adducts undergo oxidation at the 3-isoindolone position after activation of the amide by triflic anhydride and 2-chloropyridine to form a pentadienyl cation capable of undergoing a halo-Nazarov cyclization. Using this methodology, angular-fused N-heterocyclic small molecules with two new rings, two new carbon-carbon bonds, a vinyl halide, and an aza-tertiary stereocenter can be obtained in good yields.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.