Dimethyl Sulfate → 3-Hydroxymethyl-1-methyl-7-trifluoromethyl-4-quinolone

Participants

Reaction Steps

Dimethyl sulphate (24.4 g.) was added over 5 minutes to a stirring solution of 4-hydroxy-3-hydroxymethyl-7-trifluoromethylquinoline (23.6 g.) and potassium hydroxide (16.3 g.) in a mixture of water (50 ml.) and tetrahydrofuran (50 ml.) at room temperature. After stirring for a further 3 hours at this temperature the solid product was collected. The filtrate was extracted with dichloromethane (3×200 ml.). The combined extracts were dried over anhydrous magnesium sulphate and evaporated to give a second crop of the solid. The combined solids were purified by high pressure liquid chromatography over silica gel, eluting with isopropanol: dichloromethane 10:90 at a flow rate of 200 ml. per minute. The same solvent was used for applying the product to silica gel. This procedure gave the novel 3-hydroxymethyl-1-methyl-7-trifluoromethyl-4-quinolone, m.p. 172°-175°.

Provenance & Evidence