Research on Synthetic Process of 2,5-Dioxo-1,4-cyclohexanedicarboxylic Acid Dimethyl Ester

The process for synthesis of 2,5 dioxo 1,4 cyclohexanedicarboxylic acid dimethyl ester was carried out by reacting sodium methylate with dimethyl succinate in the presence of excess dimethyl succinate used as reaction solvent.The effects of raw material ratio,reaction temperature and reaction time on the yield of the product were studied.Under the optimized process conditions molar ratio of dimethyl succinate to sodium methylate=4 3∶1 0,reaction temperature 100 ℃ and reflux time 25-30 min,2,5 dioxo 1,4 cyclohexanedicarboxylic acid dimethyl ester of high purity(≥97 5%) was obtained in a high yield of 88 1% based on sodium methylate.