Hydrochloric Acid → 2-(6-Methyl-2-p-tolyl-imidazo[1,2-a]pyridin-3-yl)-5-oxo-pentanoic acid methyl ester

Participants

Reaction Steps

To a magnetically stirred solution of (+/−)-4-[1,3]dioxolan-2-yl-2-(6-methyl-2-p-tolyl-imidazo[1,2-a]pyridin-3-yl)-butyric acid methyl ester 35b (0.10 g, 0.253 mmol) in acetone (5 mL) at room temperature under Ar atmosphere was slowly added 5N HCl (1.5 mL). The reaction mixture was stirred for 2 h and then concentrated in vacuo to remove acetone. NaHCO3 solution (100 mL) was added until the pH is greater than 9, and the aqueous phase was extracted with ethyl acetate (2×100 mL). The combined organic layers were washed with water, dried (MgSO4), and concentrated in vacuo to provide 0.064 g (75%) of the crude product. 1H NMR (400 MHz, CDCl3) δ 2.24 (m, 4H), 2.34 (s, 3H), 2.39 (s, 3H), 3.70 (s, 3H), 4.38 (t, J=8.1 Hz, 1H), 7.03 (d, J=1.4 Hz, 1H), 7.24 (d, J=7.3 Hz, 2H), 7.56 (m, 3H), 7.99 (s, 1H), 9.48 (s, 1H).

Provenance & Evidence