Phosphonic acids and esters. XX. Preparation and ring opening reactions of .alpha.,.beta.- and .beta.,.gamma.-epoxyalkylphosphonates. The proton magnetic resonance spectra of vicinally substituted ethyl- and propyl-phosphonates
osmium-catalyzed dihydroxylation has uncovered that electron-deficient olefins are converted into the corresponding diols much more efficiently when the pH of the reaction medium is maintained on the acidic side. Further studies have identified citric acid as the additive of choice, for it allows preparation of very pure diols in yields generally exceeding 90%. As described here, a much wider range of olefin classes