Disclosed is a process for preparing dianthranilate compounds which comprises (a) admixing reactants as follows: (1) a diol of the formula R.sub.1 (OH).sub.2, wherein R.sub.1 is an alkylene group having at least about 20 carbon atoms, and wherein the --OH groups are primary or secondary, (2) isatoic anhydride, present in an amount of at least, about 2 moles of isatoic anhydride per every one mole of diol, (3) a catalyst which is 1,4-diazabicyclo [2.2.2]octane, N,N,N',N'-tetramethylethylene diamine, or a mixture thereof, said catalyst being present in an amount of at least about 0.2 mole of catalyst per every one mole of diol, and (4) a solvent; and (b) heating the mixture thus formed to form a dianthranilate compound of the formula ##STR1## Also disclosed is a process for preparing diazopyridone colorants which comprises (I) preparing a dianthranilate compound by the aforementioned method, (II) reacting the dianthranilate compound with nitrosylsulfuric acid to form a diazonium salt, and (III) reacting the, diazonium salt with a pyridone compound to form a diazopyridone compound.
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