Removing Organotin By-Products

In this example, reaction solvent is evaporated and the tetradeutero-adamantane and tri-n-butyltin bromide dissolved in ether and washed with saturated KF in water (ca. 10 g in 100 ml). The resulting polymeric tri-n-butyltin fluoride is insoluble in both water and organic solvent and is removed by filtration under vacuum. The desired product is then purified by sublimation. 

Anyone who has tried this method will know that it is not as straightforward as it appears. The fluoride wash is biphasic and rarely removes all organotin residues from the organic extract. The organotin fluoride 

Trialkyltin hydroxide is in equilibrium with hexaalkylditin oxide and both are retained by column chromatography on silica, together with excess DBU and DBU hydroiodide. 

MeCN/pentane partition silica column aq, KF work-up silica column KF/siIlea column 

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