Alkynylorganotins, versatile precursors of class II hybrid materials

In the field of functional organic-inorganic hybrid materials, recent trends in the chemistry based on trialkynylorganotins 1 and organically bridged alpha,omega,w-bis(trialkynyltin) compounds 2 are reviewed. Compounds 1 reacted with non-porous silica and nanoporous tin dioxide powders to yield hydrophobic, lipophobic or perylene dye-modified oxide materials. The formation of M-oxide-O-Sn-C bonds and the release of three molecules of alkyne led to the irreversible chemisorption of 1, the reaction rate and the chain loading depending on the electronic demand and the bulkiness of the organic group grafted. Furthermore, self-assembled tin-based class II hybrid materials were spontaneously formed by hydrolysis of 2 under homogeneous conditions as the two tin atoms were bridged through a rigid or a semi-rigid linker. Subsequent thermal treatment of these hybrids under an oxygen flow at 400-500 degrees C furnished nanoporous tin dioxide materials consisting of a porous network of aggregated cassiterite tin dioxide particles. An unusual polymodal distribution of mesopore sizes was found in the case of the sample prepared from the hybrid containing the diphenylene spacer. Copyright (c) 2007 John Wiley & Sons, Ltd.