40006-64-2Relevant academic research and scientific papers
4-Ylidenebutenolide Syntheses, I. Simple Synthesis of Unsaturated Bicyclic Orthoesters and Their Acidic Hydrolysis to Fused 4-Alkylidene-2-buten-4-olides
Saalfrank, Rolf W.,Schierling, Peter,Schaetzlein, Petra
, p. 1463 - 1467 (2007/10/02)
Reaction of (2,2-diethoxyvinylidene)triphenylphosphorane (4) with enolizing cyclic 1,2-diketones 5 via the (2,2-diethoxyvinyl)triphenylphosphonium enolates 8 yields the orthoester phosphoranes 11, which in an intramolecular Wittig reaction spontaneously give the fused orthoesters 7, whose acidic hydrolysis affords the 4-alkylidene-2-buten-4-olides 2.
