1H-Imidazole-5-carboxylicacid,1-(1-methylethyl)-(9CI) synthesis

Yield:105293-80-9 59%

Reaction Conditions:

in pyridine;thionyl chloride;chloroform;Petroleum ether;

Steps:

1.a (a)

(a) N-(2,4-dichlorophenyl)-1-isopropyl imidazole-5 carboxamide 1-Isopropyl-5-imidazolecarboxylic acid (2.1g) was heated under reflux in thionyl chloride (35ml) for 21/2 hours. Excess thionyl chloride was evaporated off and the residue was added to a solution of 2,4-dichloroaniline (2.2g) in dry pyridine (25ml). The reaction was refluxed for 18 hours, allowed to cool and poured onto ice. The aqueous solution was extracted with ethyl acetate (3x100ml) and the combined organic extracts were washed with water (3x200ml) and dried (MgSO₄) and the solvent was evaporated off under reduced pressure leaving a brown oil. Column chromatography on silica using chloroform as eluant afforded a colourless oil which crystallized on scratching in ether/petroleum ether to afford white crystals of N-(2,4-dichlorophenyl)-1-isopropyl imidazole-5-carboxamide (2.4g, 59%), m.p. 77-78°C;

References:

EP191514,1991,B1