Title Selective Coupling of β‐(Borylvinyl)silanes by a Gold‐catalyzed Hiyama Reaction – An Easy Way to Diaryl‐Substituted Vinyl Boronates

Diaryl‐substituted vinyl boronates as potent building modules are challenging to synthesize. Herein, we present a convenient strategy based on a gold‐catalyzed Hiyama arylation of (Z)‐β‐(borylvinyl)silanes which are easily accessible by hydroboration of silylalkynes. By exploiting the highly electronegative nature of the Au(III) intermediate (which is accessed by the light‐assisted oxidation with aryl diazonium salts), a selective activation of the silyl group in the presence of the boron moiety is achieved. This opens a route to selectively synthesize diaryl‐substituted vinyl boronates. The reaction shows a broad substrate range, excellent functional group tolerance and perfect chemo‐selectivity. Experimental studies and DFT calculations allowed us to elucidate the mechanism of the reaction, the synthetic potential was demonstrated by downstream transformations providing a facile route to bifunctional phenanthrenes and triaryl‐substituted olefins.