Cu(II)-Promoted Cascade Synthesis of Fused Imidazo-Pyridine-Carbonitriles

J Org Chem. 2021 Dec 3;86(23):17504-17510. doi: 10.1021/acs.joc.1c02198. Epub 2021 Nov 1.

Abstract

A Cu(II)-promoted synthesis of an aza-fused N-heterocycle having a benz-imidazopyridine scaffold is developed via an addition-cyclization reaction followed by an Ullmann-type C-N coupling between o-iodoanilines and γ-ketodinitriles. This protocol features a broad substrate scope, giving products in 32-84% yields. The compounds show excellent photoluminescence properties having two absorption maxima in the region between 270-280 and 338-350 nm and emission maxima in the range of 502-533 nm. The HOMO-LUMO energy gap of 3.49-3.57 eV was determined using Gaussian 09 at the B3LYP/6-31G (d, p) basis set level. We also demonstrated a few postsynthetic modifications.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cyclization
  • Imidazoles*
  • Molecular Structure
  • Pyridines*

Substances

  • Imidazoles
  • Pyridines
  • imidazopyridine