Monomeric, oligomeric and polymeric radical anion salt prodn. - by reducing naphthalene tetra:carboxylic di:anhydride or bis:imide cpd. with dithionite

摘要

Prodn. of monomeric radical anion salts of formula (I) or oligomeric or polymeric radical anion salts contg. units of formulae (II) and (III), derived from naphthalene-1,4,5, 8-tetracarboxylic dianhydride or bisimide, involves reducing monomeric naphthalene-tetracarboxylic acid derivs. (IV) or oligomeric or polymeric naphthalene-tetracarboxylic acid derivs. (V) with alkali dithionites (VI) in aq. medium with pH above 7: K = a cation neutralising negative charge of anion, which may be substit. bound chemically to cation; B = -O- or -NR1-; R1 = (substd.) (ar)alkyl or phenyl; R = a substit.; c and m = =, 1, 2, 3 or 4; R2 = 1-6C alkylene or -R3-X-R3-; R3 = 1-4C alkylene; X = O, S or -NR4-; R4 = H, 1-4C alkyl, 1-4C acyl or omega-dimethylamino-(1-4C)-alkyl. ADVANTAGE - Salts can be produced easily and economically. Redn. is almost quantitative under these conditions, even though (IV) and (V) are insol. in water. Salts have electrical conductivity than those prepd. by electrochemical redn. or chemical redn. with alkali metals or organic cpds. rich in electrons.