HCID 22061439, compound → HCID 18314450, compound

Participants

Reaction Steps

2.14 g of 3,6-di-(4′-chlorophenyl)-pyrrolo[3,4,c]pyrrole-1,4-dione (Pigment Red 254), 7.26 g of 4-heptyl pyrocarbonate from Example B1, 0.30 g of 4-dimethylaminopyridine and 150 ml of dry tetrahydrofuran are mixed and the mixture is stirred at room temperature for 165 minutes. The suspension is filtered through a glass microfilter supporting a cotton filter, the solvent is evaporated off under reduced pressure and the residue is admixed with 50 ml of isopropanol. After 16 hours the precipitate is filtered off with suction and dried under reduced pressure to leave 1.90 g (49% of theory) of 2,5-di-4-heptyloxycarbonyl-3,6-di-(4′-chlorophenyl)-pyrrolo[3,4,c]pyrrole-1,4-dione as orange crystals. NMR (CDCl3) [ppm]: δ=7.67 (d,4H), 7.46 (d,4H), 4.98 (m,2H), 1.55 (m,8H), 1.30 (m,8H), 0.90 (t,6H).

Provenance & Evidence