Avoid water or alcohol, as TMS reagents react with active hydrogen.
Avoid enolizable ketones.
Use dimethylformamide for steroids and other large molecules.
Use dimethylsulfoxide to prepare TMS derivatives of tertiary alcohols and some compounds with low solubility in other silylation solvents.
Pyridine is an excellent solvent and reaction medium for MS reactions and is an HCI acceptor in reactions involving organochlorosilanes.
Other commonly used solvents include tetrahydrofuran and acetonitrile.