Water → 3-(9,10-Didehydro-2-formyl-6-methyl-8alpha-ergolinyl)-1,1-diethylurea

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Reaction Steps

Under argon, 1.10 g (2.5 mmol) of 3-[9,10-didehydro-2-(1,3-dithiolan-2-yl)-6-methyl-8α-ergolinyl]-1,1-diethylurea is dissolved in 25 ml of chloroform and combined with 1.9 g of silica gel of a particle size of 0.063-0.2 mm. Under vigorous agitation, 2 ml of distilled water is added dropwise. Subsequently, within a time period of 15 minutes, a solution of 0.5 ml (0.6 mmol) of sulfuryl chloride in 13 ml of chloroform is added dropwise and the mixture is stirred for 2 hours at room temperature. For working-up purposes, 3 g of potassium carbonate is added and the mixture is vigorously agitated for 20 minutes. The precipitate is filtered off and washed with methylene chloride. The precipitate is moistened with ethanol and made into a slurry with 250 ml of saturated sodium chloride solution. This mixture is repeatedly extracted with methylene chloride. The extracts are dried together with the methylene chloride filtrate over magnesium sulfate and concentrated. The crude product is chromatographed under pressure on silica gel with a chloroform/methanol mixture and the main fraction of 448 mg is recrystallized from diisopropyl ether, thus obtaining 225 mg of 3-(9,10-didehydro-2-formyl-6-methyl-8α-ergolinyl)-1,1-diethylurea (25% yield).

Provenance & Evidence