A Universal Organocatalyst for Selective Mono-, Di- and Tri-Boration of Terminal Alkynes

Multiboronate compounds are valuable synthetic building blocks for the construction of complex organic architectures via cross-coupling chemistry at C-B bonds. Hence, there has been a tremendous amount of work in the past decades to develop practical multiboration reactions. Many of developed methods start from alkynes, the most versatile synthetic precursors for multiboronates, and use transition-metal complexes as catalysts. However, several drawbacks such as low efficiency, poor selectivity and narrow substrate and catalyst scopes remain major challenges to be ad-dressed in this research area. Herein, we report the development of a universal organocatalytic system to promote the mono-, di- and tri-boration of terminal alkynes in highly efficient and selective manner. The reaction outcomes can be manipulated at will by varying catalyst loading, reagent stoichiometry and reaction time.