Photoinduced Site-Selective Alkylation Enabling Synthesis of C-3-Alkylated Quinoxalinone on DNA

A mild and biocompatible strategy for the site-selective alkylation of quinoxalinones via photoinduced dehydrogenative alkylation has been developed. This protocol enables the functionalization of both unprotected quinoxalinone and nonreactive dihydroquinoxalinone under DNA-compatible conditions. The optimized reaction proceeds efficiently while tolerating a diverse range of alkyl donors from various radical precursors. Given its simplicity and DNA compatibility, this methodology offers a platform for the construction of DNA-encoded libraries incorporating a privileged quinoxalinone scaffold.