Selective mono-functionalization of 1,1,3,3-tetramethyldisiloxane (TMDSO) with vinyl and allyl metalloids via hydrosilylation reaction is reported. The activities of a number of transition metal catalysts in the reactions between TMDSO and selected unsaturated metalloids were determined, which permitted selection of the most efficient catalysts whose use led to selective formation of monofunctionalized disiloxanes with the regioselectivity control. All products were isolated and fully characterized by NMR spectroscopy and MS technique. (c) 2020 Elsevier Inc. All rights reserved.