Visible‐Light‐Promoted C(sp<sup>3</sup>)−H Alkylation by Intermolecular Charge Transfer: Preparation of Unnatural α‐Amino Acids and Late‐Stage Modification of Peptides
Chao Wang, Rupeng Qi, Hongxiang Xue, Yuxuan Shen, Min Chang, Yaqiong Chen, Rui Wang, Zhaoqing Xu
Abstract
Abstract Disclosed herein is the visible‐light‐promoted deaminative C(sp 3 )−H alkylation of glycine and peptides using Katritzky salts as electrophiles. Simple reaction conditions and excellent functional‐group tolerance provide a general strategy for the efficient preparation of unnatural α‐amino acids and precise modification of peptides with unnatural α‐amino‐acid residues. Mechanistic studies suggest that visible‐light‐promoted intermolecular charge transfer within a glycine–Katritzky salt electron donor‐acceptor (EDA) complex induces a single‐electron transfer process without the assistance of photocatalyst.
Topics & Concepts
ChemistryAlkylationElectrophileGlycineAmino acidIntermolecular forceVisible spectrumSalt (chemistry)Combinatorial chemistryAcceptorElectron transferStereochemistryPhotochemistryOrganic chemistryMoleculeCatalysisBiochemistryPhysicsOptoelectronicsCondensed matter physicsRadical Photochemical ReactionsCatalytic C–H Functionalization MethodsSulfur-Based Synthesis Techniques