Halophosphines reduction

In general, if the desired carbon—phosphoms skeleton is available in an oxidi2ed form, reduction with lithium aluminum hydride is a powerful technique for the production of primary and secondary phosphines. The method is appHcable to halophosphines, phosphonic and phosphinic acids as well as thein esters, and acid chlorides. Tertiary and secondary phosphine oxides can be reduced to the phosphines. 

Reduction of halophosphines [34-37] or alkyl phosphonates [38] using lithium aluminum hydride is commonly employed for the preparation of alkyl or aryl substituted primary phosphines (Eqs. 1-4) ... 

Organosilanes and HSiClj reduce selectively halophosphines, phosphonous acids and phosphonic acids and estersUnlike ionic metal hydrides, organosilanes do not attack C—P bonds. The organosilane reductions usually can be performed without solvents. In addition, they occur with retention of configuration at the phosphorus. 

Specialty-chemical level production (kilograms) of phosphines is achieved by hydride reductions of halophosphines, phosphonyl halides and esters and phosphinyl halides and esters, e.g. ... 

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