Patent ID: 6255482
Filing Date: 2001-07-03
Classification: C07D,C09B

Abstract:
A process for preparing a triphendioxazine compound of formula (I) ##STR29##in which the rings labeled A in positions 1,2-, 2,3- or 3,4- and 8,9-, 9,10- or 10,11- carry a linearly or angularly fused heterocyclic ring containing at least one nitrogen atom which is substituted or unsubstituted, provided that compounds with only unsubstituted nitrogen atoms and symmetrically disubstituted compounds with C.sub.1-2 alkyl and unsubstituted phenyl substituents are excluded,said process comprising:following reacting two moles of a compound the formula (IV) ##STR30##in which ring A carries a fused heterocyclic ring containing at least one nitrogen atom which is substituted or unsubstituted, provided that compounds with only unsubstituted nitrogen atoms and symmetrically disubstituted compounds with C.sub.1-2 alkyl and unsubstituted phenyl substituents are excluded,with one mole of 2, 3, 5, 6-tetrachloro-1,4-benzoquinone (chloranil) ##STR31##where the rings labeled A are as defined above,conducting the cyclization of the compound of the formula (XVII) to the compound of the formula (I) ##STR32##in the presence of manganese dioxide and concentrated sulphuric acid.