Oxidative Control of Photoinduced Cascade Electrocyclizations in Aromatic Azido Imines to Access Complex Fused Imidazoles or Pyrazoles

Org Lett. 2024 Apr 5;26(13):2558-2563. doi: 10.1021/acs.orglett.4c00361. Epub 2024 Mar 26.

Abstract

Photoinduced cascade of two 6π-electron six- and five-center electrocyclizations in aromatic azido imines is oxidatively controlled to yield complex fused benzimidazoles or indazoles. Formation of benzimidazoles occurs via an unprecedented carbon-to-nitrogen o-iminoaryl 1,2-shift.