초임계 이산화탄소에서의 유기인 일리드와 카르보닐 화합물의 반응

Abstract

The condensation reaction of (benzylene)triphenylphosphoranes with carbonyl compounds in super-critical carbon dioxide was examined. Reactions of (benzylene)phosphoranes (ca. 1 mmol) with several benzaldehydesin a supercritical carbon dioxide (80oC, 2,000 psi) containing THF entrainer (5%) in a 24 mL reactor proceed smoothlyto yield olefination products in fairly good to excellant yields but slower, compared to reactions in a conventional THFZ)-selective reactions with aro-matic aldehydes under scCO2 condition than in THF. The reaction of (benzylene)triphenylphosphoranes with 4-t-butyl-cyclohexanone gave the corresponding olefin compounds with a low conversion under both the supercritical carbondioxide and the organic THF solvent. Our preliminary study showed the Wittig reaction carries out smoothly in super-critical carbon dioxide medium and also a possibile tunability of this reaction pathway by adding a entrainer. The resultswould be useful for devising a novel process for the environmentally friendly Wittig reaction.