Methyl p-toluenesulfonate → HCID 20201050, compound

Participants

Reaction Steps

9.5 Parts of 1,4-diketo-3,6-di-(3'-methylphenyl)pyrrolo-[3,4-c]pyrrole, 9 parts of anhydrous potassium carbonate and 24 parts of methyl p-toluenesulfonate are heated at 190° C. with 85 parts of nitrobenzene for 1 hour, with stirring. The cooled reaction mixture is filtered. The dye formed remains dissolved in the solvent. The nitrobenzene is removed by means of steam distillation and the crude dye is purified by crystallisation from 45 parts of toluene. 3.8 parts of 1,4-diketo-2,5-dimethyl-3,6-di-(3'-methylphenyl)pyrrolo-[3,4-c]-pyrrole are obtained in the form of orange crystals of melting point 195°-197° C. (formula XIII). The dye gives a pure yellow shade of good fastness properties on PES by the method described in Example 1b. ##STR17##

Provenance & Evidence