| 摘要 |
A new route for preparation of 3:2,4-bis-(3,4- dimethylbenzylidene) sorbitol [DMDBS] has been disclosed which is comprising: bromination of o-xylene to obtain a mixture of 4-bromo- o-xylene as a major product and 3-bromo-o-xylene; conversion of bromo-o-xylenes into corresponding dimethylbenzaldehyde by Grignard reaction; and reaction of 3,4-dimethylbenzaldehyde with sorbitol in presence of catalyst and solvent to obtain DMDBS. The invented route is cost-effective and it obviates the need to separate 3,4-dimethylbenzaldehyde from its 2,3-isomer. |
