Phosphonomethylated 5-tert-Butylfuranyl Aldoesters: Preparation and Use in the Synthesis of Hybrid Heterocyclic Systems

Abstract

Phosphorylated derivatives of furanсarbaldehydes and furanylacetic aldehydes containing an ester and tert-butyl groups in the ring were synthesized. Their behavior in the Wittig reaction with resonance-stabilized acylmethylenetriphenylphosphoranes was studied. The resulting furanylalkenes are heterocyclic analogues of trans-chalcones. The compounds obtained by reaction with acetylmethylenetriphenylphosphorane were used as starting substrates for the synthesis of (E)-[2-(1,2,3-selenodiazol-4-yl)ethen-1-yl]furans, heterocyclic analogues of trans-stilbenes. Furanylacetic aldehydes form two isomers in the Wittig reaction, differing in the position of the double bond in the propene fragment. All obtained unsaturated ketones react with hydrazine to form 3,5-disubstituted 4,5-dihydro-1H-pyrazoles.