Application of Directed Orthometalation toward the Synthesis of Aryl Siloxanes

A selection of ortho-substituted aryl siloxanes have been prepared by directed orthometalation protocols. These siloxanes can be prepared in high yields and purity by use of a diverse selection of ortho-directing groups and electrophilic siloxane derivatives. The siloxanes are employed in palladium-catalyzed cross-coupling reactions with aryl bromides to generate unsymmetrical ortho-substituted biaryls in good to excellent yields.