1,3-Dichloro-1,1,3,3-tetraisopropyldisiloxane is a specialty organosilicon reagent used primarily as a bifunctional silylating agent to protect 1,2- and 1,3-diols in organic synthesis. It forms stable, cyclic tetraisopropyldisiloxane (TIPDS) protecting groups that are orthogonal to many other protecting groups and can be selectively removed under mild acidic conditions. This compound is widely employed in the synthesis of nucleosides, oligonucleotides, and carbohydrates for pharmaceutical, biotechnological, and medicinal chemistry applications, enabling complex molecule assembly with high efficiency and selectivity.