Nucleophilic additions to 1,3-dienes the synthesis of geranylacetone

The industrial process requires a large phosphine excess ([P]/[Rh] = 21 1) which can be easily provided by the extremely water-soluble TPPTS. However, the reactants are insoluble in such an aqueous phase, therefore the reaction is run in the presence of co-solvents, usually alcohols. (Less soluble TPPMS performs better at [P]/[Rh] = 3, probably its surfactant properties help in solubilizing the diene and methyl acetoacetate.) The organic products are easily separated from the aqueous catalyst solution which can be recycled. 

Grieco, ed., Organic Synthesis in Water, Blackie Academic and Professional, London, 1998 

Organic Reactions in Aqueous Media, Wiley, New York, 1997 

Lubineau, J. Auge, in Aqueous-Phase Organometallic Catalysis (B. Comils, W. A. Herrmann, eds.), Wiley-VCH, Weinheim, 1998, p. 19 

Beletskaya, A. V. Cheprakov, in Organic Synthesis in Water (P. A. Grieco, ed.), Blackie Academic and Professional, London, 1998, p. 141 

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