Clonidine → 1H-Imidazol-2-amine, 4,5-dihydro-N-(2,6-dichlorophenyl)-1-(2-quinolinylcarbonyl)-

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Reaction Steps

2.85 g (16.5 millimoles) of quinoline-2-carboxylic acid are dissolved in 200 ml of absolute tetrahydrofuran, 2.7 g (16.5 millimoles) of N,N'-carbonyl-diimidazole are added and the mixture is stirred for 45 minutes at room temperature. A solution of 3.75 g (16.5 millimoles) of 2-(2',6'-dichlorophenylamino)-2-imidazoline in 75 ml of absolute tetrahydrofuran is then added dropwise and the batch is stirred overnight. Thereafter, the reaction solution is freed from solvent on a rotary evaporator and the oily residue is introduced into 200 ml of an 0.5% strength sodium bicarbonate solution. The crystalline crude product (5.2 g) is filtered off and recrystallized from N,N-dimethylacetamide/isopropanol, and the crystals are washed with cold isopropanol. 3.3 g of 1-(quinolin-2-oyl)-2-(2',6'-dichlorophenylamino)-2-imidazoline are obtained, melting point 197°-198° C.

Provenance & Evidence