| 摘要 |
PROBLEM TO BE SOLVED: To provide a racemate of (1S, 1'S, 3S, 3'S, 4S, 4'S)dicyclohexyl-3,3',4,4'- tetracarboxylic acid dianhydride (trans-DCDA-2) and (1R, 1'R, 3R, 3'R, 4R, 4'R)-dicyclohexyl-3,3',4,4'-tetracarboxylic acid dianhydride (trans-DCDA-3) which is useful as a raw material of polyimide resin or the like and its precursor, a racemate of corresponding tetracarboxylic acids (trans-DCTA-2 and trans- DCTA-3) as well as their production method. SOLUTION: A racemate of methyl esters of trans-DCTA-2 and trans-DCTA-3 is hydrolyzed to obtain the racemate of trans-DCTA-2 and trans-DCTA-3. The obtained racemate is dehydrated to obtain the racemate of trans-DCDA-2 and trans-DCDA-3. |
