Triphosgene → 1-(4-(trifluoromethyl)-2-(piperidin-1-yl)benzyl)-3-(3,4-dihydro-3-oxo-2H-benzo[b][1,4]oxazin-8-yl)urea

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Reaction Conditions

Reaction Steps

Amine 2c (420 mg, 1.6 mmol) (Scheme 7) was dissolved in 20 ml of AcOEt and at 0° C. triphosgene (475 mg, 1.6 mmol) was added to the solution. The mixture was warmed at 80° C. for 4 hours then evaporated and dissolved in 5 ml of DMF. The solution of the isocyanate was added drop wise to a solution in DMF (10 ml) of compound 1f (180 mg, 1.1 mmol) and the mixture was warmed at 80° C. for 8 hours. (TLC AcOEt 1/petroleum ether 1). The solvent was evaporated and the crude was dissolved in AcOEt (30 ml) and washed with water (1×20 ml) and brine. The organic phase was dried over sodium sulfate and concentrated under vacuum. The purification of the crude residue by chromatographic column gave 160 mg of a white solid. Yield=32% 1HNMR (DMSO, 200 MHz) δ 1.57 (2H, bs), 1.68 (4H, bs), 2.85 (4H, m), 4.39 (2H, d, J=5.6 Hz), 4.62 (2H, s), 6.47 (1H, dd, J=7.8 Hz, J′=1.2 Hz), 6.81 (1H, t, J=8 Hz), 7.31 (2H, m), 7.43 (2H, m), 7.74 (1H, dd, J=8.4 Hz, J′=1.2 Hz), 8.18 (1H, bs), 10.65 (1H, bs); [M+1] 449.2 (C22H23F3N4O3 requires 448.4).

Provenance & Evidence