Synthesis of some 4H,10H[1]benzoxepino[3,4‐c]pyrazol‐4‐one derivatives

Abstract 1 H (or 2 H )4 H 10 H [1]Benzoxepino[3,4‐ c ]pyrazol‐4‐ones were prepared from phenoxymethylpyrazolecarboxylic acids which in turn were synthesized from simple starting materials. Different pathways to allow the predominant formation of the N‐1 or N‐2 substituted derivatives are described. The isomeric 1 or 2‐substituted structures were supported by 13 C‐nmr.