A Study of Phosphites

Grant, David (1962) A Study of Phosphites. PhD thesis, University of Glasgow.

Abstract

1) The pyrophosphite anion is greatly modified as compared to the pyrophosphate anion as regards its tendency to form metal complexes in solution; pyrophosphite is a relatively weak ligand, (p. 57-81). 2) The P-O-P bond in the pyrophosphite unit will not tolerate further attachment of P-O-P bonds as in the condensed phosphates, (cfp 100-119). 3) The P-H bond in the phosphite ion undergoes two types of reaction leading to formation of higher oxy-acids of phosphorus, namely breakdown to gaseous phosphine, this occurs where there are P-OH groups attached to the phosphorus, or to gaseous hydrogen, where there are no P-OH groups present, in this latter case the formation of P-P bonds is favoured in the reaction product, (c.f. 112-119). 4) The kinetics of the oxidative breakdown of phosphorous acid have been elucidated in terms of a radical chain reaction, (c.f.p 107-112). 5) During the study of pyrolysis of metal phosphites numerous compounds have been prepared, simple and more complex salts of phosphorous acid which have not been described before. The properties of several salts which have been described in the literature have been more thoroughly investigated than heretofore. 6) Two types of hydrates of pyrophosphorous acid seem to be obtained best described as H-P-O-P-H (cfp 87). and types based on the P-O-H3O+ structure, (c.f.p 85). 7) For the series of alkali metal hydrogen phosphites and the corresponding alkaline earth salts the ease of P-O-P bond formation on heating is related in a simple way to the sizes of the cations, (cfp 91-99). Oxidative breakdown of the P-H bonds in these compounds and others are related to the same function of cations size, cross relationships between the ease of reaction and infra-red spectral data are also found particularly with the cases of P-H reactions, (c.f. 96). 8) Sublimation of phosphorous acid has been investigated. The maximum amount of sublimation occurs when the pressure over the acid is such as to allow sublimation but retard the formation of pyrophosphorous acid, (cfp 100-106). 9) An unknown spot has been obtained on the acid chromatograms of products from the pyrolysis of phosphorous acid. It appears in advance of pyrophosphate in acid elutions, and probably corresponds to an unknown phosphorous oxy- anion, (c.f.p 183-191). 10) Pyrolysis of Rb2HPO3 leads to a product containing most of the original oxidation-reduction equivalent of the original product but no P-H bonds are detectable by infrared spectroscopy (cfp 196-197).

• Item Type: Thesis (PhD)
• Qualification Level: Doctoral
• Keywords: Inorganic chemistry
• Date of Award: 1962
• Depositing User: Enlighten Team
• Unique ID: glathesis:1962-79430
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 05 Mar 2020 09:56
• Last Modified: 05 Mar 2020 09:56
• URI: https://theses.gla.ac.uk/id/eprint/79430