Improved Preparation of 4,6,6-Trimethyl-1,3,2-Dioxaborinane and its Use In a Simple PdCl2(TPP)2-Catalyzed Borylation of Aryl Bromides and Iodides
Résumé
We describe a convenient preparation of 4,6,6-trimethyl-1,3,2-dioxaborinane (MethylPentaneDiolBorane, MPBH) and demonstrate that MPBH is an excellent reagent for the PdCl2(PPh3)2 catalyzed borylation of aryl bromides and iodides. The corresponding boronic esters readily undergo rapid Suzuki coupling in the presence of cesium fluoride. Thus, MPBH is an excellent alternative to Pinacolborane for Pd-catalyzed borylation and cross-coupling reactions.