Base and Ligand-Free Silver-Catalyzed Csp-H Thiolation of Terminal Alkynes with N-Thiosuccinimides.

This work presents an efficient and sustainable protocol for the direct Csp-H thiolation of terminal alkynes with N-thiosuccinimides via silver catalysis. The reaction proceeds under mild, base-, and ligand-free conditions, enabling the construction of alkynyl sulfides in good to excellent yields. The key advantages of this protocol are that it enables the omission of external bases and ligands, offers operational simplicity, and maintains broad functional group tolerance. This method offers a simple and effective alternative for synthesizing versatile alkynyl sulfide derivatives, with potential applications in pharmaceutical and materials chemistry.