| 摘要 |
Cyclohexa - 1,4 - diene - 1,4 - dicarboxylic acid is made by contacting cyclohexane-2.5-diol-1,4-dicarboxylic acid or an acid ester or diester thereof with a hydroxide or an alkoxide of an alkali metal or an alkaline earth metal at 100-150 DEG C. and neutralizing the product. Sodium hydroxide is preferably employed in aqueous solution of 1N-5N concentration. Calcium, strontium, and barium hydroxides, and alkoxides of 1-4 carbon atoms are referred to. Solvents specified are water and alcohols of 1-4 carbon atoms. In examples, dimethyl cyclohexane-2,5-diol-1,4-dicarboxylate is (1) heated with aqueous caustic soda, and (2) sodium methoxide in methanol.
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