Cyclohexasiloxanes with long alkyl chains and triethoxysilyl groups were synthesized by alkoxysilylation of organometallasiloxanes containing cyclohexasiloxanes. Lamellar mesostructured siloxane-based materials were formed by self-assembly of these cyclosiloxane compounds through hydrolysis and polycondensation. This molecular design will lead to the creation of siloxane-based materials with cavities that can be used for inclusion and separation of guest species.