5-methyl-3-phenyl-6-(2-pyridyl)-isoxazolo[4,5-c]pyridin-4(5H)-one → 3-(alpha-iminobenzyl)-4-hydroxy-6-(2-pyridyl)-1-methyl-2(1H)-pyridone

Participants

Reaction Steps

A mixture of 16.5 g. (0.0545 mole) of 5-methyl-3-phenyl-6-(2-pyridyl)-isoxazolo[4,5-c]pyridin-4(5H)-one, 330 ml. ethanol and 1.65 g. 10% palladium on carbon is hydrogenated at 50 psi and room temperature. The hydrogenation is ceased after one equivalent of hydrogen is absorbed (ca. 2.5 hours). The mixture is treated with methylene chloride and the catalyst is removed by filtration. The solvents are removed in vacuo to a volume of ca. 50 ml. and then ether is added, to precipitate solids which are removed by filtration to give 3-(α-iminobenzyl)-4-hydroxy-6-(2-pyridyl)-1-methyl-2(1H)-pyridone; m.p. 242° to 245° C. In order to obtain the sodium salt of the aforementioned compound, for example, the compound is dissolved in methanol and treated with sodium hydroxide solution to yield after evaporation the sodium salt.

Provenance & Evidence