Tert-Butyldimethylsilyl chloride

tert-Butyldimethylsilyl chloride is an organosilicon compound with the formula (Me3C)Me2SiCl (Me = CH3). It is commonly abbreviated as TBSCl or TBDMSCl. It is a chlorosilane containing two methyl groups and a tert-butyl group. As such it is more bulky that trimethylsilyl chloride. It is a colorless or white solid that is soluble in many organic solvents but reacts with water and alcohols. The compound is used to protect alcohols in organic synthesis.

tert-Butyldimethylsilyl chloride reacts with alcohols in the presence of base to give tert-butyldimethylsilyl ethers:
 * (Me3C)Me2SiCl +  ROH  →   (Me3C)Me2SiOR  +  HCl

These silyl ethers hydrolyze much more slowly than the trimethylsilyl ethers.

It also can silylate terminal alkynes.

Related reagents
The triflate derivative (Me3C)Me2SiOTf is used similarly but is more reactive.