摘要 |
<p>1,8-dinitro-2-chloroanthraquinones (1,5-(I) and/or 1,8-(I) respectively) are prepd. by the nitration of 5- and/or 8-nitro-2-chloroanthraquinone (5-(II) and/or 8-(II) respectively). The (II) used are free from 2-chloroanthraquinones contg. NO2 gps. in other posns. of the mol. Process gives excellent yields of high purity 1,5-(I) and/or 1,8-(I) free from other isomers which normally have to be removed by fractional crystallisation. Prepd. (I) are of higher purity than the prods. obtained in GB 1189072. In an example, 1,5-(I) (5.75 pts.) was prepd. by adding 96% HNO3 (2.65 pts.) to 5-(II) (5-75 pts.) in 98% H2SO4 (57.5 pts.), then heating the mixt. for 12 hr. at 80-85 degrees C.</p> |