Silica-anchored organotin trichloride: a recyclable and clean organotin catalyst for transesterification reactionsElectronic supplementary information (ESI) available: CP-MAS 117Sn NMR spectra and TG mass loss data. See DOI: 10.1039/c3dt50292a

A new synthetic scheme towards silica-supported organotrichlorotin derivatives has been developed. It involves the synthesis of (11-triethoxysilyl)undecyltricyclohexyltin, followed by solgel processing and, subsequently in the formation of the resulting hybrid silica, by electrophilic substitution of the tricyclohexyltin function by the target grafted trichlorotin using tin tetrachloride. HR-MAS 119 Sn and CP-MAS 29 Si NMR combined with N 2 -sorption and TEM measurements evidenced the formation of a mesoporous organicinorganic hybrid silica including a functionally pure supported-organotrichlorotin species. This silica-grafted organotrichlorotin displays a satisfactory catalytic activity in the transesterification of ethyl acetate by 1-octanol. The catalyst could be recycled four times without significant loss of activity. Furthermore, tin leaching below 10 ppm evidences the benefits of the proposed strategy to limit tin contamination of the final products. A new synthetic scheme towards silica-supported organotrichlorotin derivatives has been developed.