Octadecyltrichlorosilane (ODTS or n-octadecyltrichlorosilane) is an organosilicon compound with the formula CH3(CH2)17SiCl3.
A colorless liquid, it is used as a silanization agent to prepare hydrophobic stationary phase, for reversed-phase chromatography.
[2] It is also evaluated for forming self-assembled monolayers on silicon dioxide substrates.
It is flammable and hydrolyzes readily with release of hydrogen chloride.
Dodecyltrichlorosilane, an ODTS analog with shorter alkyl chain, is used for the same purpose.