A novel synthesis of (E)-gem-dimetalloalkenes containing boron and silicon

ORGN 458

Narayan G. Bhat, Amanda Tamm Tamm, and Amanda Gorena. Chemistry, University of Texas-Pan American, 1201 West University Drive, Edinburg, TX 78539
A simple, novel synthesis of (E)-gem-dimetalloalkenes containing boron and silicon based on Z-1-bromo-1-alkenylboronate esters is developed. Alpha-bromo-(Z)-1-alkenylboronate esters readily available from literature procedures smoothly undergo a reaction with trimethylsilyllithium (easily generated from hexamethyldisilane with methyllithium in hexamethylphosphoramide) to provide the corresponding tetracoordinated boron complexes. These complexes undergo intramolecular nucleophilic substitution reaction to provide the corresponding (E)-1-alkenylboronate esters containing trimethylsilyl moiety in good isolated yields (72%-85%).