Synthesis of quaternary carbon-centered indolo[1,2- a]quinazolinones and indazolo[1,2- a]indazolones via C-H functionalization

Chem Commun (Camb). 2021 Feb 11;57(11):1388-1391. doi: 10.1039/d0cc07419e.

Abstract

An unprecedented Ru(ii)-catalyzed Csp2-H bond activation and annulation reaction of phenylindazolones with diaryl-substituted alkynes and dialkyl-substituted alkynes provided efficient routes for the construction of all-carbon quaternary-centered indolo[1,2-a]quinazolinones and quaternary carbon-centered indazolo[1,2-a]indazolones, respectively. The indolo[1,2-a]quinazolinones were fomed via Csp2-H activation, alkyne insertion and a 1,2-phenyl shift. Indazolo[1,2-a]indazolones were formed through a cascade reaction via the formation of exocyclic double bonds containing indolo[1,2-a]quinazolinones.