Patent ID: 8227626

Claim:
A process for preparing a compound according to the general formula (I-a) or (I-b), where R 1 , R 2 , R 3 , R 4 are each independently H, CN, NO 2 , NH 2 , Br, CH 3 , CF 3 , OCH 3 , OCF 3 , CHO, COOH, COOR, NHCOCH 3 , or SO 2 CH 3 , where R is a C 1 -C 4 -alkylene, and X is H, Cl or F, comprising: reacting a dihydroxy compound of the general formula (II-a) where R 5 , R 6 , R 7 , R 8 are each as defined above, with an optionally substituted dihalomethane or formaldehyde; and optionally, chlorinating a methylene group, and/or fluorinating a methylene group.