A minireview on diketopyrrolopyrrole chemistry: Historical perspective and recent developments

In this review, we described the synthesis of various 2,5-dihydropyrrolo[3,4-c]pyrrole-1,4-dione diketopyrrolopyrroles (DPPs). We begin with a discussion of the various synthetic protocols collected for DPPs, we discuss first method is the Reformatski reaction and then followed by other routes. Later, we discussed the functionalization of DPP building blocks via N-alkylation along with aromatic substituents at the 3- and 6-positions and also explored modification at the carbonyl groups utilising diverse catalysts. We also give the brief importance of DPPs in high-quality pigments and the detailed reactions of DPPs with electrophiles, nucleophiles, and metal-catalyzed coupling reactions. Nevertheless, there has been magnificent development in the field of DPPs with respect to modification to the core (3- and 6-positions) and also in ketone position of DPPs, which tune their optical and photophysical properties. That may eventually suitable for future development of solar cells for real world applications to meet tomorrow's energy demand to supply to community.