HCID 68157677, compound → HCID 68157387, compound

Participants

Reaction Steps

A solution of [(S)-1-(2-o-tolylaminopyridin-3-ylcarbamoyl)ethyl]carbamic acid tert-butyl ester (2.51 mmol) in AcOH (20 mL) was heated at 70° C. for 6 h. After cooling to RT, the volatiles were removed under reduced pressure and the residue partitioned between DCM and a saturated aqueous solution of NaHCO3. The aqueous phase was extracted with DCM and the combined organic fractions washed with water, dried (Na2SO4) and concentrated in vacuo to afford [(S)-1-(3-o-tolyl-3H-imidazo[4,5-b]pyridin-2-yl)ethyl]carbamic acid tert-butyl ester as a brown oil (quantitative). To a solution of the compound thus obtained (2.51 mmol) in DCM (25 mL) was added TFA (10 mL) and the mixture stirred at RT for 15 min. The volatiles were removed in vacuo and the resulting residue dissolved in DCM and washed with a saturated aqueous solution of NaHCO3 (40 mL). The aqueous phase was further extracted with DCM (×3) and the combined organic fractions dried (Na2SO4) and concentrated in vacuo. The resulting residue was purified by column chromatography (Si—PCC, gradient 0-8% 2M NH3/MeOH in DCM) to afford the title compound as an oil (340 mg, 54% over 3 steps). 1H NMR (CDCl3, 400 MHz): δ 8.33 (1H, d, J=4.83 Hz), 8.09 (1H, d, J=8.00 Hz), 7.52-7.37 (3H, m), 7.33-7.21 (2H, m), 4.08 (0.5H, q, J=6.75 Hz), 3.99 (0.5H, q, J=6.72 Hz), 2.02 (3H, s), 1.50 (1.5H, d, J=6.75 Hz), 1.41 (1.5H, d, J=6.75 Hz). Signals split due to presence of rotamers/tautomers.

Provenance & Evidence