| 摘要 |
A process for the transesterification of a carboxylic or carbonic acid ester comprises reacting the carboxylic or carbonic acid ester under transesterification conditions with an alcohol in the presence, as catalyst, of either (i) a Group V element-containing Lewis base and an epoxide or (ii) a cyclic amidine. The Lewis base can be an organic compound containing trivalent phosphorus or nitrogen and can be an amine, for example an amidine. The process can be operated in the liquid phase at a temperature of from 15 DEG to 150 DEG C., and the catalyst is employed in solution. Preferred catalysts are those where the cyclic amidine forms part of a fused ring system containing six and five membered rings, six and seven membered rings or two six membered rings. |
