Deprotection method for hydroxy groups protected

A deprotection method comprising treating an alcohol having a hydroxyl group protected with a t-butyldimethylsilyl group to remove the t-butyldimethylsilyl group, in the presence of a solvent, where the deprotection is carried out in the presence of an acid or salt acid having a pKa of 1.0 to 3.0 in water, and wherein the solvent is capable of dissolving at least 1% vol water at room temperature and is a nitrile.