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The study introduces a previously unidentified method for amide bond formation that addresses several limitations of conventional approaches. It uses the β-silyl alkynoate molecule, where the alkynyl group activates the ester for efficient amide formation, while the bulky TIPS (triisopropylsilane) group prevents unwanted 1,4-addition reactions. This approach exhibits high chemoselectivity for amines, making the method compatible with a wide range of substrates, including secondary amines, and targets the specific ε-amino group of lysine among the native amino ester's derivatives. It maintains stereochemistry during amide bond formation and TIPS group removal, allowing a versatile platform for postsynthesis modifications such as click reactions and peptide-drug conjugations. These advancements hold substantial promise for pharmaceutical development and peptide engineering, opening avenues for research applications. [ABSTRACT FROM AUTHOR]

Introduction of an iodine(III) reagent as visible‐light photocatalyst for chemoselective dithioacetalization has been the limelight of the current methodology. The mechanistic investigations reveal that the reactions proceeded via radical pathway upon light induced hemolytic cleavage of C–I bond of the catalyst. Several dithioacetals were easily accessible at room temperature and environmentally benign condition. [ABSTRACT FROM AUTHOR]

An umpolung approach for the synthesis of unsymmetrical disulfides via sulfenium ion is reported. In situ generated electrophilic sulfenium ion from electron‐rich thiols reacted with second thiols to yield unsymmetrical disulfides. Using an iodine catalyst and 4‐dimethylaminopyridine (DMAP)/water as promoter, the target syntheses were achieved in one pot under aerobic condition. [ABSTRACT FROM AUTHOR]

Herein we report the use of N‐iodosuccinimide (NIS) as a bifunctional reagent for a regio‐ and (E)‐selective C(sp2)‐H sulfonylation reaction of styrenes. Styrenes and sulfonyl hydrazides treated with NIS and potassium carbonate in ethanol at 70 °C resulted in (E)‐vinyl sulfones exclusively with good to excellent yields. NIS, plays a dual role to generate sulfonyl radical from sulfonyl hydrazides at an initial stage and finally gives β‐iodosulfone intermediate which was further converted to (E)‐vinyl sulfones. Overall, a sustainable method for mild, metal free, convenient, one pot and direct synthesis of (E)‐vinyl sulfones from styrenes are demonstrated via a C−S coupling reaction. Double trouble: N‐iodosuccinimide (NIS) is introduced as a bifunctional reagent towards development of a direct approach of functionalizing C(sp2)‐H of styrene in a regio‐ and (E)‐selective manner. [ABSTRACT FROM AUTHOR]