Methanol → Methyl pyrrole-2-carboxylate

Participants

Reaction Conditions

Reaction Steps

A suspension of 1H-pyrrole-2-carboxylic acid (5.5 g, 49.5 mmol), WSCI.HCl (12.2 g, 63.6 mmol), HOBt (8.4 g, 62.2 mmol), methanol (7.0 g, 218 mmol) and 4-dimethylaminopyridine (3.0 g, 24.5 mmol) in dimethylformamide (60 ml) was stirred for 70 hours at room temperature and for 2 hours at 60° C. To the reaction mixture was added an aqueous 5% potassium hydrogensulfate solution and the mixture was extracted with ethyl acetate/toluene (1/1). The organic layer was washed with an aqueous saturated sodium hydrogencarbonate solution, and an aqueous saturated sodium chloride solution, and dried over magnesium sulfate. The solvent was removed and the residue was purified with silica gel chromatography (hexane:ethyl acetate=5:1→3:1) to give the subject compound (4.88 g, 79%).

Provenance & Evidence