Acetic Acid → Tert-butyl 4-{[5-(2-chlorophenyl)-1-(2,6-dichlorophenyl)-2-oxo-1,2,3,4-tetrahydroquinazolin-7-yl]methyl}-3-methylpiperazine-1-carboxylate

Participants

Reaction Steps

A solution of 5-(2-chlorophenyl)-1-(2,6-dichlorophenyl)-2-oxo-1,2,3,4-tetrahydroquinazoline-7-carbaldehyde (Intermediate AAA1, 208 mg, 0.48 mmol) and 1-BOC-3-methylpiperazine (96 mg, 0.48 mmol) in dichloroethane (5 mL) was stirred at rt for 30 min. To this was added sodium triacetoxyborohydride (150 mg, 0.67 mmol) followed by acetic acid (29 mg, 0.48 mmol). The resulting reaction mixture was stirred at rt for 20 h. The reaction was quenched with 2N NaOH solution (6 mL) followed by extraction with ethyl acetate (100 mL×2). The organic layer was washed with brine and dried over anhydrous sodium sulfate. Removal of the solvent and subsequent purification by flash chromatography using 25% acetone/hexane provided tert-butyl 4-{[5-(2-chlorophenyl)-1-(2,6-dichlorophenyl)-2-oxo-1,2,3,4-tetrahydroquinazolin-7-yl]methyl}-3-methylpiperazine-1-carboxylate as a white solid. 1H NMR (CDCl3, 500 MHz): δ 0.98 (s, 3H), 1.46 (s, 9H), 2.06 (brs, 1H), 2.39 (brs, 1H), 2.60 (brs, 1H), 2.82 (brs, 1H), 3.05 (brs, 1H), 3.15 (m, 1H), 3.54 (brs, 2H), 3.82 (brs, 1H), 4.34 (abq, 2H, J=14.2 Hz), 5.15 (s, 1H), 6.16 (d, 1H, J=5.2 Hz), 6.88 (s, 1H), 7.20-7.60 (m, 7H). MS (API-ES+): 617 (M+H).

Provenance & Evidence