| abstract |
Carboxylic acid compounds, each of which has an indenenskeleton and represented by the following formula (2) or anfluorene skeleton and represented by the following formula (3),nare each prepared by reacting an unsaturated carboxylic acidncompound represented by the following formula (1) with indenenor fluorene in the presence of a strong base catalyst:n nwherein R 1 , R 2 , R 3 and R 4 each independently represents an atomnor group selected from a hydrogen atom, an alkyl group, an arylngroup or a carboxyl group, with the proviso that at least onenof R 3 and R 4 contains a carboxyl group or a salt thereof or ancarboxylic ester group. |