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