Syntheses of Organic Phosphates. II. 3-Hydroxy-2-pyridylmethyl, 6-Methyl-2-pyridylmethyl, 3-Pyridyl and 8-Quinolyl Phosphate

Abstract

The phosphorylation of 3-hydroxy-2-pyridylmethanol and 6-methyl-2-pyridylmethanol was carried out with pyrophosphoric acid. 3-Pyridinol and 8-quinolinol were phosphorylated in pyridine by using five- to ten-fold molar amount of phosphoryl chloride at room temperature or below. The chromatographic elution of the reaction mixtures on a column of cation-exchange resin, with water as an eluent, was found to be effective for separation and purification of the products in most cases, while 8-quinolyl phosphate was obtained directly from the concentrated reaction mixture. These phosphates, with the exception of 3-hydroxy-2-pyridylmethyl phosphate, follow acid dissociation processes similar to the case of pyridylmethyl phosphates. The effect of the 3-hydroxy group in 3-hydroxy-2-pyridymethyl phosphate on its acid dissociation processes was discussed. A symmetric pyrophosphate ester was also isolated in the course of phosphorylation of 3-pyridinol.