Hydrochloric Acid → 6-Fluoro-2-methyl-2,3-dihydroquinolin-4(1H)-one

Participants

Reaction Conditions

Reaction Steps

A stirred solution of 25.8 g (0.146 mole) of 6-fluoro-4-methoxyquinoline from example 3 in 300 ml of tetrahydrofuran was heated under a nitrogen atmosphere to its reflux temperature and then cooled to -20° C. To the cold solution was added 90 ml of 182 M methyl lithium in diethyl ether over a period of 0.5 hour. After adding 40 ml of the solution, the reaction temperature was allowed to rise to 0° C. After the addition of methyl lithium was completed, the reaction temperature was allowed to rise to 15° C. The solution was then poured into 1200 ml of a mixture of ice water and hydrochloric acid. After stirring for 0.5 hour the mixture was extracted with about 1200 ml of diethyl ether. The organic layer was dried, filtered and evaporated in vacuo to provide a yellow solid. The product was recrystallized from carbon tetrachloride to give 9.5 g. (37% yield) of 6-fluoro-2-methyl-4-oxo-1,2,3,4-tetrahydroquinoline.

Provenance & Evidence