Highly regio- and chemoselective silylation of diethyl α-hydroxyphosphonates, alcohols and phenols in the presence of solid TiCl3(OTf) as a catalyst with hexamethyldisilazane (HMDS) at room temperature in the absence of solvent

Solid trichlorotitanium(IV) trifluoromethanesulfonate [TiCl3(OTf)] is an easily prepared compound from the reaction of TiCl4 with trifluoromethanesulfonic acid. This solid Ti(IV) based compound is used as a catalyst for highly efficient silylation of diethyl α-hydroxyphosphonates, alcohols and phenols with hexamethyldisilazane (HMDS) at room temperature under solvent-free conditions. Chemo- and regioselectivity for masking different hydroxyl functional groups were observed in the presence of this catalyst.