Trimethylsilyl derivatives of polyhydric alcohols are conveniently prepared in good yield from the polyol and trimethylchlorosilane in the presence of a tertiary amine such as pyridine. They are very stable, easily distillable liquids, or low-melting solids. Representatives of each of the following classes of trimethylsilyl derivatives were prepared; mono-and bis-(trimethylsilyl) derivatives of glycols; polytrimethylsilyl derivatives of tri-, tetra-, and hexa-hydric alcohols; trimethylsilyl derivatives of bis-(/3-hydroxyethyl) dicarboxylates. These substances are particularly useful in problems involving the separation and purification of difficultly isolable polyols. Schenectady, N. Y.