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

Key words

tetracyclic scaffolds - privileged structures - atom-economical­ syntheses - dibenzo[b,f][1,4]oxazepines - Smiles rearrangement - nucleophilic aromatic substitution - denitrocyclization - regiospecific reaction

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