Synthesis and applications of phosphines in environmentally benign catalysis

Synthesis and applications of phosphines in environmentally benign catalysis 

The first class of water soluble ligands to be prepared were sulfonated triphen-ylphosphine derivatives.59 These have been studied in great detail, and even used industrially. 

These ligands are made by the addition of oleum to the appropriate aryl phosphine (Protocol 6). The reaction is difficult to control as a number of substitution products are possible, and the phosphines are susceptible to oxidation under the reaction conditions. It should be noted that impure, uncharacterized ligands of this type are often used successfully in catalysis. 

Caution All procedures should be carried out in a well-ventilated hood, and disposable vinyl or latex gloves and chemical-resistant safety goggles should be worn. 

Ensure that all glassware is thoroughly clean and has been dried for at least 4 h in a 120°C oven before use. Assemble glassware while still hot. 

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