esters to terminalalkynes can be switched by the choice of phosphorus ligands on the palladium catalysts. The silaboration proceeds with normal regioselectivity in the presence of (eta(3)-C(3)H(5))Pd(PPh(3))Cl (1.0 mol %) to give 1-boryl-2-silyl-1-alkenes in high yields. In sharp contrast, selective formation of the inverse regioisomers, 2-boryl-1-silyl-1-alkenes, takes place when the reaction is carried
Double take: β‐Borylallylsilanes have been synthesized by the regioselective silaboration of terminal alkynes followed by palladium‐catalyzed double‐bondmigration of the resulting β‐borylalkenylsilanes (see scheme). The stereoselectivity of the double‐bondmigration can be controlled by additives, thus leading to the stereocomplementary synthesis of (E)‐ and (Z)‐β‐borylallylsilanes.