| Abstract
| - Trialkynyl(fluoroorgano)tins(IV) (C4H9−C⋮C)3−SnRF (1) (RF = −(CH2)2−CF3, −o-FC6H4)have been synthesized in three steps from tricyclohexyltin hydride or chloride and werecharacterized by multinuclear 1H, 13C, 19F, and 119Sn NMR spectroscopy. Hydrolysis of 1yielded oxo-hydroxoorganotin oligomers soluble in acetonitrile and alcohols, where each tinatom bears a fluorinated organic group. Thermally induced β- or γ-elimination reactions,evidenced by TG/MS measurements, allowed the insertion of fluorine into the oxide networkand the removal of the undesirable organics. Densification at 550 °C gave crystalline particlesof SnO2 cassiterite containing the required amount of doping fluorine (4 at. %) and exhibitingan electronic resistivity (0.3 Ω·cm) lower than that previously reported (2−10 Ω·cm) forsimilar tin oxide materials. β- or γ-elimination processes in organotin compounds appear tobe a suitable method of preparation of highly conductive nanocrystalline F-doped SnO2materials by the sol−gel route with low contaminating carbon content.
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