Synthesis of N,N-dimethylaminopyrene-modified short peptides for chemical photocatalysis.

The synthesis of peptide-based photocatalysts that use 1-N,N-dimethylaminopyrene as chromophore and their application in photocatalysis is reported. The copper(I)-catalyzed alkyne-azide cycloaddition was applied as key step to prepare the peptide-pyrene conjugates in quantitative yields for different short peptide sequences. The photocatalysts were evaluated for the nucleophilic addition of methanol to 1,1-diphenylethylenes to products with Markovnikov-type orientation The short peptides contain arginine as substrate binding site during photocatalysis, and thus, the reaction was performed without the additive triethylamine that was previously applied as electron shuttle. Full conversion of the substrate and good yields for the addition product were achieved.