The Dissociation, Distribution, and Dimerization Constants of Some Organophosphorus Acids

In a pre\u27V.ious paper1 the values of . the acid dissociatiOIIl constants of several esters of orthophosphoric aciid were given, as well as .the values of their dimerization aind distriibut1o!Il constants :i!Il chlorofol\u27!Il. Recellltly someother or.ganophosphmms acids have been prepared i.e. two .phospholllic acid esters R(RO)P.OOH and two pho1sphinic acids R,POOH and their characterishc constairuts determilned

Base Strength of Various Organic Oxides

The protonation constants pKa of various aromatic substituted organic oxides are reported. The following order of increasing basicities of the investigated organic oxides was established: sulphoxides, phosphine oxides, pyridine-N-oxides, selenoxides, arsine oxides, antimony oxides and tellurium oxides. Several effects, affecting the base strength of the investigated organic oxides, such as back donation, electronegativity of the element, its polarizability and inductive effect of the radicals bound to the element are discussed

Base Strength of Various Organic Oxides

The protonation constants pKa of various aromatic substituted organic oxides are reported. The following order of increasing basicities of the investigated organic oxides was established: sulphoxides, phosphine oxides, pyridine-N-oxides, selenoxides, arsine oxides, antimony oxides and tellurium oxides. Several effects, affecting the base strength of the investigated organic oxides, such as back donation, electronegativity of the element, its polarizability and inductive effect of the radicals bound to the element are discussed

Investigation on the Extraction of Metal Ions with Different Organophosphorus Compounds. I. The Dissociation, Distribution and Dimerization of Some Di-aryl Esters of Orthophosphoric Acid

The net distribution ratio q of several di-aryl esters ot orthophosphoric acid between chloroform and 1 M (or 0.1 M) HC104 - NaC104 solutions has been studied. The distribution of the acids has been measured spectrophotometrically, except in the case of di-(benzyl) phosphate, where a radiometric method has been applied using acid labelled with 32P. Varying the composition of the aqueous and the organic phase a number of data were obtained from which, by fitting the normalized curve log y = log (x + 1), the dissociation, distribution and dimerization constants of the investigated acids were calculated. The values of these constants are given in Table II. Following the equation given by Hammett, the strength as well as the association of the investigated acids can be satisfactorily explained assuming that the inductive polar effect of the substituents affects their dissociation and dimerization constants. The results allow to predict the values of these constants for the orthophosphoric acids carrying other substituents