| 摘要 |
Keto acids and/or unsaturated lactones are prepared by reacting ethylene or propylene, at a partial pressure of at least 100 atmospheres, with carbon monoxide in the presence of a catalyst comprising a palladium salt of a strong acid in solution in a liquid phase, in the substantial absence of free acid or base. The preferred palladium salts are palladous chloride, bromide or iodide. The preferred solvents are neutral ones, e.g. nitromethane, acetonitrile or propionitrile. Water is preferably absent from the reaction medium, though if keto acids are the desired product, a minor proportion of water of, at most, ten moles per gram atom of palladium should be present. Preferably the palladium is present in concentration from 0.1 to 1 gram atom per litre of liquid medium. The preferred temperature range is from 80 DEG to 200 DEG C. The molar ratio of ethylene or propylene to carbon monoxide is preferably from 10:1 to 0.1:1. Examples describe the preparation of a ,b , b ,g and g ,d -homoangelica lactones, 4-keto hexanoic acid and a mixture of unsaturated lactams of formula CH12O2. |
