Author(s)

Tomoji Ohishi^1*, Yu Kimura¹, Kiyohiko Nakajima², Masayuki Watanabe³, Noboru Aoyagi³

¹Department of Applied Chemistry, Faculty of Engineering, Shibaura Institute of Technology, Tokyo, Japan.
²Department of Chemistry, Aichi University of Education, Kariya, Japan.
³Nuclear Science and Engineering Center, Sector of Nuclear Science Research, Japan Atomic Energy Agency, Naka-gun, Ibaraki, Japan.

A high-efficiency synthesis method for a latent pigment of red pigment diketo-pyrrolo-pyrrole (Pig. Red 272:272DPP), which is important as a functional organic pigment, was investigated, and the investigation results revealed that irradiation of microwaves (MWs) for several seconds to 272 DPP in NMP (N-methyl-2-pyrrolidone) solvent yielded DPP latent pigment (272DPP-BOC) at a high yield of 86.2%. Two kinds of latent-pigment crystals, namely, red and yellow, were obtained by recrystallization, and it was found that the fluorescence-emission properties of the two kinds differ significantly. Single-crystal X-ray structural analysis showed that the difference in the fluorescence-emission properties of the two types is derived from the difference in their crystal structures.

Latent Pigment, Diketopyrrolopyrrol, Pigment Red 272, High Efficiency Synthesis, Microwave Irradiation, Single-Crystal X-Ray Analysis

Ohishi, T. , Kimura, Y. , Nakajima, K. , Watanabe, M. and Aoyagi, N. (2020) High-Efficiency Synthesis and Properties of Latent Pigment Red 272DPP-BOC by Microwave Irradiation. Materials Sciences and Applications, 11, 195-203. doi: 10.4236/msa.2020.113013.