Dibenzo[b,f]pyrazolo[1,5-d][1,4]oxazepines: Facile Construction of a Rare Heterocyclic System via Tandem Aromatic Nucleophilic Substitution-Smiles Rearrangement-Denitrocyclization

Abstract

Condensation of 2-(1<i>H</i>-pyrazol-5-yl)phenols with 1-chloro-2-nitrobenzenes under basic conditions in <i>N</i>,<i>N</i>-dimethyl­formamide results in a tandem, atom-economical, aromatic nucleophilic substitution–Smiles rearrangement–denitrocyclization process to provide pyrazolo-fused dibenzo[<i>b</i>,<i>f</i>][1,4]oxazepines as a single regioisomer.