Oligomerization of oxiranes in the presence of phosphorus acids, 2. Kinetics of addition of ethylene oxide to phosphoric and phosphorous acid

Abstract

AbstractKinetics of addition of ethylene oxide to the POH groups in phosphorous (H3PO3) and phosphoric acid (H3PO4) were studied. The reaction is catalysed by the POH groups themselves, presumably by formation of hydrogen‐bonded complexes with ethylene oxide. The values of apparent rate constants of reactions involving subsequent POH groups were determined. The apparent reactivity of POH increases with increasing number of OCH2CH2OH substituents present in the reacting molecule. This has been attributed to the formation of intramolecular hydrogen bonds influencing the reactivity of the POH groups. Mechanistic implications and the distribution of products are discussed in connection with the observed kinetic dependences.