Methane → Imidafenacin

Participants

Reaction Steps

Into a mixture of 32 mL of 1 mol/L hydrochloric acid and 101 mL of purified water, 13.3 g (32.0 mmol) of 4-(2-methyl-1-imidazolyl)-2,2-diphenylbutanamide phosphate obtained in Example 3 were dissolved, and 1.33 g of activated charcoal were added. After stirring for 1 hour, the mixture was filtered through 4 cm-size Kiriyama funnel, in which 2.66 g of cellulose powder was laid and washed with 13 mL of purified water. To the filtrate and washed solutions 130 mL of ethanol were added, and, under stirrings 48 mL of 2 mol/L sodium hydroxide solution were added to neutralize the solution and crystallize out of the solution. After stirring for 1 hour at an inner temperature of below 15° C. under cooling with ice water, the crystals were collected by filtration and washed with 50 mL of 40% ethanol, then with each 200 mL of purified water five times (fifth washed solution: pH 8.80). Into 53 mL of ethanol, 10.6 g of wet crystals were dissolved completely by heating, and the solution was stirred for 1 hour at room temperature to crystallize out of the solution, followed by cooling with ice water. After stirring for 1 hour at an inner temperature of below 15° C., the crystals were collected by filtration and washed with 5 mL of ethanol. The crystals were dried for 3 hours at 60° C. under reduced pressure (vacuum pump) to obtain 7.80 g (yield: 76.3%) of 4-(2-methyl-1-imidazolyl)-2,2-diphenylbutanamide as white crystalline powder.

Provenance & Evidence