HCID 14500628, compound → HCID 14500629, compound

Participants

Reaction Conditions

Reaction Steps

To a stirred suspension of 2 g (50 mmol) of lithium aluminum hydride in 100 ml of anhydrous tetrahydrofuran was added dropwise, at room temperature and under nitrogen atmosphere, a solution of 9 g (45 mmol) of 1-methyl-2-(3'-aminobenzoyl)pyrrole in 100 ml of anhydrous tetrahydrofuran. The reaction mixture was refluxed for 15 minutes, cooled to 0° C. and the excess reagent destroyed by carefully adding ethyl acetate, saturated sodium sulfate solution and solid anhydrous sodium sulfate. The insoluble material was separated by filtration and the filtrate evaporated in vacuo. The unstable 1-methyl-2-(3'-amino-α-hydroxybenzyl)pyrrole thus obtained (9 g, 45 mmol) was dissolved in 150 ml of methanol, cooled to 0° C. and treated with 24 ml (419 mmol) of glacial acetic acid and 5.67 g (90 mmol) of sodium cyanoborohydride. The reaction mixture was stirred at room temperature for 18 hours, poured into 500 ml of saturated sodium carbonate solution and the product extracted with ethyl acetate (3×500 ml). The combined extracts were washed with water (3×300 ml), dried and evaporated in vacuo. The residue was purified by column chromatography on 600 g of silica gel, using hexane-ethyl acetate (80:20) as eluant, obtaining 4.89 g (67%) of the title compound, 1-methyl-2-(3'-aminobenzyl)pyrrole, which was recrystallized from acetone-hexane.

Provenance & Evidence