C3H9SiCl

C3H9SiCl, also known as chlorotrimethylsilane or TMSCl, is an organosilicon compound with the chemical formula (CH3)3SiCl. It is a colorless, volatile liquid with a pungent odor. TMSCl is a key reagent in organic synthesis and is widely used in chemistry laboratories.

The primary use of chlorotrimethylsilane is as a silylating agent. It reacts with hydroxyl (-OH), amino (-NH2), and thiol (-SH) groups to form trimethylsilyl ethers, amines, and thioethers, respectively. This process, known as silylation, is often employed to protect functional groups during chemical reactions or to increase the volatility of compounds for analysis by gas chromatography. The trimethylsilyl group is easily removed under mild acidic or basic conditions, making it a convenient protecting group.

Chlorotrimethylsilane is also used in the synthesis of other organosilicon compounds, including silicone polymers. It serves as a precursor for various silanes and siloxanes. Its reactivity stems from the polar silicon-chlorine bond, which is susceptible to nucleophilic attack.

Industrially, TMSCl is produced by the direct process, reacting methyl chloride with silicon in the presence of a copper catalyst. It is a flammable liquid and should be handled with appropriate precautions in a well-ventilated area, as it reacts readily with moisture to produce hydrochloric acid.