Sodium hydride → Tert-butyl 4-{[5-(2-chlorophenyl)-1-(2,6-dichlorophenyl)-2-oxo-1,2,3,4-tetrahydroquinazolin-7-yl]methylene}piperidine-1-carboxylate

Participants

Reaction Steps

To a solution of diethyl [5-(2-chlorophenyl)-1-(2,6-dichlorophenyl)-2-oxo-1,2,3,4-tetrahydroquinazolin-7-yl]methylphosphonate (422 mg, 0.762 mmol) in a mixture of THF (9 mL) and DMF (2 mL) at 0° C. was added sodium hydride (60%, 61 mg, 1.52 mmol). The resulting mixture was stirred at rt for 20 min and then cooled to 0° C. again. To this was added a solution of t-butyl-4-oxo-1-piperidinecarboxylate (310 mg, 1.524 mmol) in THF (2 mL). Then the reaction was stirred at rt for 22 h. The mixture was quenched with brine, and extracted with ethyl acetate. The organic layer was washed with brine and dried over anhydrous sodium sulfate. Removal of the solvent and subsequent purification by flash chromatography using 20% acetone/hexane as eluent provided tert-butyl 4-{[5-(2-chlorophenyl)-1-(2,6-dichlorophenyl)-2-oxo-1,2,3,4-tetrahydroquinazolin-7-yl]methylene}piperidine-1-carboxylate as a white solid. 1H NMR (CDCl3, 500 MHz): δ 1.48 (s, 9H), 2.24 (brs, 2H), 2.31 (t, 2H, J=5.7 Hz), 3.31 (t, 2H, J=5.5 Hz), 3.45 (t, 2H, J=5.5 Hz), 4.35 (abq, 2H, J=14.4 Hz), 5.10 (s, 1H), 5.96 (s, 1H), 6.21 (s, 1H), 6.74 (s, 1H), 7.30-7.58 (m, 7H). MS (API-ES+): 600 (M+H).

Provenance & Evidence