Phosphonite
Phosphonites are organophosphorus compounds with the formula P(OR)2R. They are found in some pesticides and are used as ligands.
Although they are derivivatives of phosphonous acid (RP(OH)2), they are not prepared from such precursors. Phosphonites are prepared by alcoholysis of organophosphinous chlorides. For example, treatment of dichlorophenylphosphine with methanol and base gives dimethyl phenylphosphonite:
Oxidation of phosphonites gives phosphonates:
Phosphonites can function as ligands in homogeneous catalysis.
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