Diisopropylethylamine → 4-(1-Cyclopropylpropyl)amino-3-nitro-2-pyridone

Temperature

25 °C

Part A. A mixture of 4-chloro-3-nitro-2-pyridone (2.0 g, 11.4 mmol), 1-cyclopropylpropyl amine hydrochloride (1.5 g, 11.4 mmol) and N,N-diisopropylethylamine (4.8 ml, 27.4 mmol) in CH3CN (50 ml) were stirred at 25° C. for 16 h and at reflux for 4 h. After cooling it was stripped in vacuo, and the residue was partitioned between EtOAc (100 mL) and H2O (50 mL). The insolubles were separated, washed with H2O and EtOAc and vacuum dried 1.51 g. The filtrate layers were separated and the aqueous layer was extracted with EtOAc (2×50 mL). The Combined extracts were washed with brine, dried over MgSO4, filtered and concd. in vacuo. The residue was washed with EtOAc (2×) and vacuum dried, to give 0.69 g, yellow solid. Combined wt. of 4-(1-cyclopropylpropyl)amino-3-nitro-2-pyridone 2.20 g, 81% yield. 1H NMR(300 MHz, dmso d6): 11.19 (1H, br), 8.94 (1H, d J=8.8 Hz), 7.33 (1H, t J=6.9 Hz), 6.03 (1H, d J=7.7 Hz), 3.18-3.24 (1H, m), 1.60-1.74 (2H, m), 1.03-1.11(1H, m), 0.91 (3H, t), 0.40-0.60 (1H, m), 0.20-0.39 (1H, m).

1. temperatureat reflux for 4 h
2. temperatureAfter cooling it
3. customthe residue was partitioned between EtOAc (100 mL) and H2O (50 mL)
4. customThe insolubles were separated
5. washwashed with H2O and EtOAc and vacuum
6. customdried 1.51 g
7. customThe filtrate layers were separated
8. extractionthe aqueous layer was extracted with EtOAc (2×50 mL)
9. washThe Combined extracts were washed with brine
10. dry with materialdried over MgSO4
11. filtrationfiltered
12. washThe residue was washed with EtOAc (2×) and vacuum
13. customdried
14. customto give 0.69 g, yellow solid

ORD record

ord-fd1b87fc2d204e20acb973bbf23c4265

Source dataset

uspto-grants-2002_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06362180B1