Patent ID: 6084134
Filing Date: 2000-07-04
Classification: C07C,Y02P

Abstract:
A process for preparing 9-anthracenecarbaldehydes of the formula (I) ##STR3## in which A represents C--R.sup.9 or N, and R.sup.1 to R.sup.9 independently of one another each represent hydrogen, halogen, C.sub.1 -C.sub.6 -alkoxy, phenyl, naphthyl, anthracenyl, C.sub.1 -C.sub.4 -alkyl or C.sub.3 -C.sub.7 -cycloalkyl, which comprises(a) reacting an anthracene derivative of the formula (II) ##STR4## in which A and R.sup.1 to R.sup.9 are each as defined in formula (I), with a solvent consisting of dimethylformamide in the presence of phosphoryl chloride,(b) hydrolyzing the resulting reaction mixture,(c) precipitating the anthracenecarbaldehyde that has formed by admixing a base to form a first precipitate,(d) filtering the first precipitate,(e) stirring the filtrate with water for 0.5 to 5 hours at 20 to 80.degree. C. to form a second precipitate, and(f) filtering the second precipitate;wherein the process results in a yield of greater than 97% and a purity of greater than 98%.