Phosphonic Acids

Phosphonous acids are a type of phosphorus-containing organic compounds . Tautomers have two general formulas: RP (O) H-OH and RP (OH) ₂ with a predominance of the first form.

Content

Physical Properties

Phosphonous acids are liquid or solid. They dissolve in organic solvents, and the lower phosphonous acids are soluble in water and act as acids of medium strength. In the ³¹ P NMR spectra for phosphonous acids, they have a doublet in the region of 15–40 m d. The spin – spin interaction constant is 400–500 Hz.

Chemical Properties

Salting :

{\mathsf {RPH(O)OH+NaOH\rightarrow RPH(O)ONa+H_{2}O}}

{\ displaystyle {\ mathsf {RPH (O) OH + NaOH \ rightarrow RPH (O) ONa + H_ {2} O}}}

disproportionate when heated

{\mathsf {2RPH(O)OH\rightarrow RPH_{2}+RP(O)(OH)_{2}}}

{\ displaystyle {\ mathsf {2RPH (O) OH \ rightarrow RPH_ {2} + RP (O) (OH) _ {2}}}}

partial oxidation to phosphonic acids

Getting

Obtained by hydrophosphylation of olefins

Application

Some phosphonous acids are used as pesticides .

Literature

Nifantiev E.E., Chemistry of organophosphorus compounds, M., 1971, p. 104-109; Nifantiev E. E., Chemistry of hydrophosphoryl compounds, M., 1983. E. E. Nifantiev
Chemical Encyclopedia / Editorial: Zefirov N.S. et al. - M .: Big Russian Encyclopedia, 1998. - T. 5 (Three-Yatr). - 783 s. - ISBN 5-85270-310-9 .