Further Study On The Synthesis Process Of DPP Pigments And Related Intermediates

DPP pigments are a class of high-grade red organic pigments with excellent performance. Compared with most of other high-grade red organic pigments, the manufacturing processes of DPP pigments are relatively simple and environmental-friendly, which might give them a chance to replace for other medium and high-grade red organic pigments to meet for the higher and higher environmental requirements. From the view of this philosophy, it is beneficial obviously to improve sustainably the synthetic process of DPP pigments and related intermediates. Based on the previous works of our team, a comprehensively improved synthetic process of DPP pigments and related intermediates were done in the present paper, including:1) a series of dialkyl succinates were synthesized and the influence of the different dialkyl succinates on the synthesis of C.I. Pigment Red264was studied;2) designing a new synthesis route to prepare4-cyanobiphenyl from N-methyl-4-phenyl-benzamide, which might greatly reduce the cost of the producing4-cyanobiphenyl by using the route;3) designing a new process of producing C.I. Pigment Red264, which might obviously simplified solvent recycling process and the influence of this process on the performance of C.I. Pigment Red264was studied as well;4) preparing a serous of DPP pigments with different shades by using physically mixing or "chemically mixing" to change their original colors and discussing the possibility of substituting some perylene pigments by these mixed DPP pigments.