Photochemically Mediated Oxidative Cross-coupling of Aminopyrazoles with 1-Thiosugars for the Synthesis of Thioglycosides

By harnessing visible-light excitation of a photocatalyst to initiate a single-electron transfer (SET) process, thereby activating glycosyl thiols to generate thiyl radicals and promote their coupling with aminopyrazoles, this work establishes an efficient photocatalytic strategy for C-S bond construction. This process involves radical addition for thioglycosyl incorporation, followed by oxidative deprotonation to furnish the target products in yields of up to 90%. Consequently, this method enables the efficient synthesis of diverse thioglycosylated pyrazole derivatives under mild conditions, exhibiting a broad substrate scope, excellent functional-group tolerance, and promising scalability, thus providing a green and sustainable synthetic approach.