Stille couplings in aqueous media

The palladium-catalyzed coupling of aryl and vinyl halides to organotin compounds, known as Stille coupling, is one of the most important catalytic methods of carbon-carbon bond formation. The reaction is generally conducted in polar organic solvents, such as dimethylformamide, with tertiary phosphine complexes of palladium, although phosphine-free complexes or simple Pd-salts are also frequently used as catalysts [8], 

In addition to all the good features of the Stille couplings, there are a few problems with the use of RSnMe3 or RSn( -Bu)3 in aqueous solutions. These compounds are rather volatile and water-insoluble but this can be overcome with the aid of co-solvents. However, the products of the reaction still contain alkyltin species which are toxic and environmentally unacceptable. Furthermore, only one of the four Sn-C units take active part in the 

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