Hydrochloric Acid → 1-(5,6-Dimethoxy-1H-benzoimidazol-2-yl-)2,2,2-trifluoro-ethanol

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

4,5-Dimethoxy-benzene-1,2-diamine (2.02 g; 12.0 mmoles) and 3,3,3-trifluoro-2-hydroxy-propionic acid (2.67 g; 18.5 mmoles) were suspended in 6N HCl (5 mL; 30 mmoles) and water (4 mL) under a nitrogen atmosphere. The reaction was stirred vigorously and heated to 108° C. for 18 hrs, then cooled to room temperature. The reaction was diluted with water (40 mL) and with ethyl acetate (40 mL), then sodium bicarbonate (3.84 g; 46.0 mmoles) was added slowly and in portions to quench the reaction. The aqueous layer was separated and extracted with ethyl acetate (3×30 mL). The extracts were combined, washed with water (30 mL) and brine (40 mL), then dried over Na2SO4. The filtrate was concentrated in vacuo to yield a crude dark orange solid which was then purified by column chromatography (SiO2; 30% ethyl acetate/CH2Cl2) to yield the title compound as a bright orange solid.

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