8-Hydroxyquinoline → 8-Hydroxy-1-methylquinolinium methyl sulfate

Participants

Reaction Steps

Into a 2-liter three-neck flask provided with a mechanical agitator, with a reflux-condenser and calcium chloride tube, and with a dropping funnel, one introduces 145 g of 8-hydroxyquinoline (i.e. 1 mole) and 200 ml of dimethyl acetamide. After dissolution of the 8-hydroxyquinoline, one cools the reaction mixture with a bath of ice water and one adds, drop by drop, by means of the dropping funnel, 126 g of freshly distilled methylsulfate (i.e. 1 mole). Shortly after the completion of the addition, a light yellow compound crystallizes little by little. One continues the agitation for 2 hours after the introduction of the methylsulfate and then leaves the mixture to rest overnight in a brine bath. The quaternary salt which is formed is dried, washed with anhydrous ether and recrystallized in methanol. Weight obtained = 219 g; Melting point = 158°C; Yield = 81%.

Provenance & Evidence