反应详情

To a mixture of [(R)-5-(5-amino-2-fluoro-phenyl)-5-difluoromethyl-5,6-dihydro-2H-[1,4]oxazin-3-yl]-carbamic acid tert-butyl ester (636 g, 1.77 mol) and 5-cyano-3-methylpyridine-2-carboxylic acid (301 g, 1.86 mol) was added THF (4.2 L) under N2 atmosphere at ambient temperature. To the stirring mixture was added N-methylmorpholine (428 mL, 3.89 mol) and the mixture was stirred to form a homogeneous solution. The reaction solution was cooled to 0-5° C. before addition of isobutyl chloroformate (256 mL, 1.95 mol) via an addition funnel while keeping the reaction temperature under 10° C. After the addition, the mixture was stirred at 0-10° C. for 1 h before filtration. The filtrate was evaporated in vacuo and the resulting residue was dissolved in the mixture of CH2Cl2 (3 L) and methanol (1 L). The mixture was concentrated in vacuo at 400 mbar/35° C. till no more volatile coming out to give a slurry. The slurry was filtered and the filter cake was washed with methanol till the wash getting colorless. The wet cake was dried in a vacuum oven at 45° C. for 24 h to give title compound as a white solid: ESIMS: 504; [(M+H)+]; 1H NMR (400 MHz, DMSO-d6): δ 10.72 (s, 1H), 10.00 (s, 1H), 8.98 (s, 1H), 8.39 (s, 1H), 7.92 (m, 1H), 7.81 (m, 1H), 7.24 (m, 1H), 6.30 (t, 1H), 4.56 (d, 1H), 4.44 (d, 1H), 4.12 (m, 1H), 3.90 (m, 1H), 2.55 (s, 3H), 1.41 (s, 9H).

1. customto form a homogeneous solution
2. customunder 10° C
3. additionAfter the addition
4. stirringthe mixture was stirred at 0-10° C. for 1 h before filtration
5. customThe filtrate was evaporated in vacuo
6. dissolutionthe resulting residue was dissolved in the mixture of CH2Cl2 (3 L) and methanol (1 L)
7. concentrationThe mixture was concentrated in vacuo at 400 mbar/35° C. till
8. customto give a slurry
9. filtrationThe slurry was filtered
10. washthe filter cake was washed with methanol till the wash
11. customThe wet cake was dried in a vacuum oven at 45° C. for 24 h