Pyruvic acid or DBU/O2 guided organophotoredox-catalyzed direct C–H alkylation/α-aminoalkylation of 1,2,4-triazine-3,5(2H,4H)-diones with amines

Abstract

An organophotoredox-catalyzed direct C–H alkylation/α-aminoalkylation of 1,2,4-triazine-3,5(2H,4H)-diones with inexpensive and easily available secondary amines as alkyl sources in the presence of different additives is reported. Both transformations are easy to scale up and suitable for the late-stage modification of bioactive molecules. Density functional theory (DFT) calculations reveal that sequential elementary steps including photoredox, pyruvic acid-assisted proton shift, C–N bond cleavage, and tautomerization are essentially involved in the transformation.