Formaldehyde → (S)-methyl 5-(4-chloro-2-cyanophenoxy)-2-methyl-6-(1-(1-methylpiperidin-4-yl)-1H-pyrazol-4-yl)-3,4-dihydroquinoline-1(2H)-carboxylate

Participants

Reaction Conditions

Reaction Steps

Formaldehyde (37% aqueous solution, 0.015 mL, 0.198 mmol) was added to a solution of (S)-methyl 5-(4-chloro-2-cyanophenoxy)-2-methyl-6-(1-(piperidin-4-yl)-1H-pyrazol-4-yl)-3,4-dihydroquinoline-1(2H)-carboxylate (0.010 g, 0.020 mmol) in methanol (1.0 mL), and the reaction mixture stirred for 2 h. The mixture was cooled to 0° C. and sodium triacetoxyborohydride (8.4 mg, 0.040 mmol) was added. The reaction mixture stirred at 0° C. and was allowed to warm to room temperature overnight. The reaction mixture was partitioned between ethyl acetate and water. The aqueous phase was extracted with ethyl acetate and the combined organic phases were washed with brine, dried over anhydrous sodium sulfate, filtered and concentrated to afford (S)-methyl 5-(4-chloro-2-cyanophenoxy)-2-methyl-6-(1-(1-methylpiperidin-4-yl)-1H-pyrazol-4-yl)-3,4-dihydroquinoline-1(2H)-carboxylate (0.0095 g, 92%) as a white solid. 1H NMR (300 MHz, DMSO-d6) δ ppm 1.06 (br d, J=6.74 Hz, 3H), 1.47-1.69 (m, 4H), 1.71-2.13 (m, 4H), 2.19 (s, 3H), 2.71-2.90 (m, 2H), 3.72 (s, 3H), 3.93-4.13 (m, 1H), 4.32-4.45 (m, 1H), 4.50-4.65 (m, 1H), 6.35-6.54 (m, 1H), 7.45-7.65 (m, 4H), 7.65-7.72 (m, 1H), 7.97 (s, 1H), 8.11 (d, J=2.64 Hz, 1H). MS (ESI, pos. ion) m/z 521 [M+H]+.

Provenance & Evidence