organic chemistry Organic chemistry is a subdiscipline within chemistry involving the science, scientific study of the structure, properties, and reactions of organic compounds and organic matter, organic materials, i.e., matter in its various forms that contain ...

, phosphonites are

organophosphorus compound Organophosphorus chemistry is the scientific study of the synthesis and properties of organophosphorus compounds, which are organic compounds containing phosphorus. They are used primarily in pest control as an alternative to chlorinated hydrocarbo ...

s with the formula P(OR)₂R. They are found in some

pesticide Pesticides are substances that are used to control pests. They include herbicides, insecticides, nematicides, fungicides, and many others (see table). The most common of these are herbicides, which account for approximately 50% of all p ...

s and are used as

ligand In coordination chemistry, a ligand is an ion or molecule with a functional group that binds to a central metal atom to form a coordination complex. The bonding with the metal generally involves formal donation of one or more of the ligand's el ...

Preparation

Although they are derivatives of phosphonous acid (RP(OH)₂), they are not prepared from such precursors. Phosphonites are prepared by

alcoholysis In chemistry, solvolysis is a type of nucleophilic substitution (S1/S2) or elimination where the nucleophile is a solvent molecule. Characteristic of S1 reactions, solvolysis of a chiral reactant affords the racemate. Sometimes however, the ster ...

of organophosphinous chlorides. For example, treatment of dichlorophenylphosphine with

methanol Methanol (also called methyl alcohol and wood spirit, amongst other names) is an organic chemical compound and the simplest aliphatic Alcohol (chemistry), alcohol, with the chemical formula (a methyl group linked to a hydroxyl group, often ab ...

and base gives dimethyl phenylphosphonite: :Cl₂PPh + 2 CH₃OH → (CH₃O)₂PPh + 2 HCl

Reactions

Oxidation of phosphonites gives

phosphonate In organic chemistry, phosphonates or phosphonic acids are organophosphorus compounds containing Functional group, groups, where R is an organic group (alkyl, aryl). If R is hydrogen then the compound is a Phosphite_ester#Chemistry_of_HP(O)(OR ...

s: :2 P(OR)₂R + O₂ → 2 OP(OR)₂R Phosphonites can function as

s in

homogeneous catalysis In chemistry, homogeneous catalysis is catalysis where the catalyst is in same phase as reactants, principally by a soluble catalyst in a solution. In contrast, heterogeneous catalysis describes processes where the catalysts and substrate are in d ...

.T. V. (Babu) Rajanbabu “Phosphinite and Phosphonite Ligands” in Phosphorus(III) Ligands in Homogeneous Catalysis: Design and Synthesis Paul C. J. Kamer and Piet W. N. M. van Leeuwen, Eds., John Wiley & Sons 2012.

References

{{Functional group Functional groups *