Substituted γ-Lactones . Some Observations on the Synthesis and Reactivity of 4-Aroyl-3-hydroxy-2(5H)-furanones
The reaction pathway towards formation of 4-aroyl-3-hydroxy-2(5H)-furanones 1 from the base catalysed reaction between an acetophenone, diethyl oxalate and formaldehyde was investigated.If methoxide was used as base, a transesterification was found to occur in the first step, while a side reaction, namely the retro Claisen reaction, was in competition with the desired lactone formation in the second step.The nature of the solvent and the acidic character of 1 as well as the basicity of the aminoarylene were found to have a product influence on the course of the reaction of 1 with aminoarylenes.
