| 摘要 |
3- 13921/1+2/+ Preparation of pyrrolo¢3,4-c!pyrroles A process for the preparation of 1,4-diketopyrrolo-¢3,4-c!pyrroles of the formula (I), wherein each of Rl and R2 independently of the other is an isocyclic or heterocyclic aromatic radical, which process comprises reacting 1 mole of a disuccinate with 2 moles of a nitrile of the formula R1 - CN (II) or R2-CN (III) or with 1 mole of a nitrile of the formula (II) and 1 mole of the nitrile of the formula (III), in an organic solvent and in the presence of a strong base at elevated temperature, and obtaining the compound of formula I from the reaction product by hydrolysis. The pyrrolo-¢3,4-c!pyrroles are suitable for pigmenting organic material of high molecular weight. |
