Aromatic nitro-group displacement reactions. Part 1. A novel route to substituted 10-phenylacridones

Abstract

Methoxy-anions in dimethyl sulphoxide initially displace the para-nitro-groups from 2,2′,4,4′-tetranitrobenzophenone (6). Primary aromatic amines however displace the two ortho-nitro-groups to give 10-aryl-3,6-dinitro-9-acridones (15), in which the nitro-groups can be displaced by anionic nucleophiles to give compounds of a previously inaccessible substitution pattern. Enhanced reactivity towards aromatic amines seems to be general in nitro-groups activated by ortho-carbonyl. Hydroxydenitration of (6) produces 3,6-dinitroxanthen-9-one (19) and 4-hydroxy-2,2′,4′-trinitrobenzophenone (20).