α ‐boryl ketones are valuable synthons in modern organic synthesis, materials science, and drug discovery. We report here a metal‐free hydration of alkynyl MIDA boronates mediated by trifluoroacetic acid, providing efficient access to α ‐boryl ketones under mild conditions. This method omits the use of transition metal catalysts, exhibits broad functional group tolerance, and proceeds through a Brønsted acid‐promoted hydration mechanism, as supported by isotopic labeling studies. The resulting α ‐boryl ketones were converted into valuable boron‐substituted heterocycles, highlighting their potential as versatile synthons in organic synthesis.
Lin et al. (Sun,) studied this question.