Phosphines and Phosphonium Salts

Organophosphorus Chemistry, Volume 33 The Royal Society of Chemistry, 2003 

Whereas the direct reaction of a-substituted alkenylzirconocene reagents with chlorophosphines does not lead to the related alkenylphosphines, two groups have now shown that if the reactions are carried out in the presence of copper(I) chloride the desired phosphines are obtained, initially as copper-complexes, from which they can be liberated by treatment with appropriate reagents. It is thought that alkenylcopper reagents are involved in these reactions, and, using this approach, new alkenylphosphines have been prepared, e.g., (41), and the diphosphines (42).  

2 Preparation of Phosphines from Metallated Phosphines. Metallophosphide reagents continue to find extensive use in the synthesis of new phosphines and, as 

As has been the pattern in recent years, there has been considerable interest in the synthesis and characterisation of phosphide reagents derived from metals other than lithium, sodium, and potassium, and also in studies of the structure of metallophosphides in the solid state. A new route to P-chiral phosphine-boranes of high enantiopurity is afforded by treatment of the borane complexes of methyl(phenyl)phosphine with a copper(I) reagent, giving the copper-phosphido intermediate (83), which, on subsequent treatment with an iodoarene in the presence of a palladium(O) catalyst, gives the related chiral t-phosphine-borane (84), with retention of configuration at phosphorus. Organophosphido systems 

Interest has also continued in the structural characterisation and synthetic application of phosphine systems which are metallated at atoms other than phosphorus. The lithio-arsenide (88) has been shown to undergo electrophilic ring-opening on treatment with alkyl halides, providing a simple route to the 

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Preparation and Properties of Organophosphines. AUphatic phosphines can be gases, volatile Hquids, or oils. Aromatic phosphines frequentiy are crystalline, although many are oils. Some physical properties are Hsted in Table 14. The most characteristic chemical properties of phosphines include their susceptabiUty to oxidation and their nucleophilicity. The most common derivatives of the phosphines include halophosphines, phosphine oxides, metal complexes of phosphines, and phosphonium salts. Phosphines are also raw materials in the preparation of derivatives, ie, derivatives of the isomers phosphinic acid, HP(OH)2, and phosphonous acid, H2P(=0)0H. 

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