Nitriles in organic synthesis: A novel synthesis of benzo[<i>h</i>]pyrimidino[1,2‐<i>c</i>]‐pyridazinone and hydrazonobut‐2‐enonitrile derivatives

Abstract

Abstract A new synthesis of benzo[ h ]pyrimidino[1,2‐ c ]pyridazinones via coupling diazotised anthranilic acid with 1‐phenylethylidenemalononitrile ( 1 ) is reported. Synthesis of new 1‐antipyrin‐4‐yl and 1‐pyrazol‐5‐ylpyridazine derivatives utilizing 1 as starting material is also described.