Ammonia → HCID 13823170, compound

Participants

Reaction Steps

Under argon, 10.74 g (23 mmol) of 3-(13-bromo-6-methyl-2-methylthio-8α-ergolinyl)-1,1-diethylurea is dissolved in 200 ml of trifluoroacetic acid. At a temperature of -15° C., sodium borohydride tablets are added thereto in 8 portions of 0.5 g each. After a reaction period of 11/2 hours at -15° C., the mixture is poured on 500 ml of ice, the solution is gently rendered alkaline with 25% strength ammonia solution, and extracted with methylene chloride. The organic phases are dried over magnesium sulfate and evaporated. The crude product is dissolved under argon in 100 ml of methanol p.a. and combined with 50 ml of 7N potassium hydroxide solution. The mixture is stirred for 2 hours at room temperature until the reaction is completed; then the mixture is poured on 150 ml of ice to work it up, and extracted with methylene chloride. The organic phases are washed with water and dried over magnesium sulfate. The concentrated crude product is chromatographed on 1.4 kg of silica gel with methylene chloride/methanol in a ratio of 97:3. In this way, 6.0 g is isolated which is crystallized from ethyl acetate/diisopropyl ether to complete the purification process, thus obtaining 5.44 g of 3-(13-bromo-6-methyl-8α-ergolinyl)-1,1-diethylurea (56% yield).

Provenance & Evidence