Water → 7-[4-Nitro-3-(trifluoromethyl)phenyl]-7-azabicyclo[2.2.1]heptane

Participants

Reaction Conditions

Reaction Steps

2-Methyltetrahydrofuran (1 vol) was charged into a 30 L jacketed reactor vessel followed by the addition of the hydrochloride salt of 4-(7-azabicyclo[2.2.1]heptan-7-yl)-2-(trifluoromethyl)aniline (3-HCl) (1.2 eq) and 4-oxo-5-(trifluoromethyl)-1,4-dihydroquinoline-3-carboxylic acid (2) (573 g, 2.228 mol). Additional 2-methyltetrahydrofuran (9 vol) was charged into the vessel and stirring commenced. T3P in 2-methyltetrahydrofuran (2 eq) was added to the reaction mixture over a period of 15 min. Pyridine (3 eq) was added rapidly in a dropwise fashion using an addition funnel. Under stirring, the mixture was then heated to 45° C. over a period of about 30 min and this temperature was maintained for about 5 h. The mixture was cooled to room temperature. 2-methyltetrahydrofuran (4 vol) was added followed by the slow addition of water (6.9 vol), and the temperature of the reaction was kept below 30° C. The water layer was removed and the organic layer was washed twice with NaHCO3 saturated aqueous solution. The organic layer was then carefully washed with 10% w/w citric acid (5 vol) and washed with water (7 vol), and polished filtered and transferred into another dry vessel. 2-methyltetrahydrofuran (10 vol) was added and stirring commenced. Heptane (10 vol) was rapidly added in a dropwise fashion with stirring. The mixture was stirred for a period of about 12 h, and then vacuum filtered. The solid filter cake was introduced into another vessel. Water (15 vol) was charged into the vessel and the suspension was stirred vigorously for 48 h, then filtered. The solid cake was washed with water (5 vol) and dried at 45° C. to constant weight to produce Compound 1 Form B.

Provenance & Evidence