Regioselective\nSynthesis of α‑Vinyl Boronates\nvia a Pd-Catalyzed Mizoroki–Heck Reaction

We report a palladium-catalyzed synthesis of α-vinyl\nboronates\nvia a regioselective Mizoroki–Heck reaction between aryl triflates\nand vinyl boronates. This selectivity is achieved by the use of a\n1,5-diaza-3,7-diphosphacyclooctane (P<sub>2</sub>N<sub>2</sub>) ligand,\nwhich results in minimal formation of the more commonly observed (linear)\nβ-product. The choice of base, solvent, and presence of water\nare shown to be critical for controlling this outcome, with organic\nbases, nonpolar solvents, and anhydrous conditions favoring the Heck\nproduct and suppressing the competitive Suzuki−Miyaura coupling\nproduct.