Triethylamine → HCID 71226405, compound

Temperature

-3 °C

To a solution of 3-methyl-1-(4-nitrophenyl)piperidine-3-carboxylic acid (2.65 g, 10.03 mmol) in THF (45 ml) cooled at −5° C. (ice/NaCl bath) was added Et3N (1.537 mL, 11.03 mmol), followed by dropwise addition of isobutyl carbonochloridate (1.443 mL, 11.03 mmol). After addition, the resulting yellow suspension was stirred at −3° C. for 75 min and then 6.25 mL of a 28% aqueous ammonium hydroxide solution (50 mmol, 5.0 equiv.) was added. The reaction mixture was stirred at ˜0° C. for 1.5 hrs. The reaction was quenched with water, the resulting mixture (pH>10) was extracted with EtOAc (3×). The combined organic phase was washed with water (2×), saturated aqueous NaCl (2×), dried over Na2SO4, filtered and concentrated. The crude product was crystallized from EtOAc to give the title compound, 3-methyl-1-(4-nitrophenyl)piperidine-3-carboxamide (777 mg, 2.95 mmol, 29.4% yield), as a brown solid. Anal. Calcd. for C13H17N3O3 m/z 263.2, found: 264.2 (M+H)+; 1H NMR (400 MHz, CDCl3) δ ppm 8.20-8.02 (m, 2H), 7.06-6.85 (m, 2H), 3.91 (d, J=13.19 Hz, 1H), 3.64-3.49 (m, 1H), 3.16 (ddd, J=12.64, 8.25, 4.40 Hz, 1H), 3.09 (s, 2H), 3.06 (d, J=13.19 Hz, 1H), 2.09 (d, J=13.74 Hz, 1H), 1.91-1.72 (m, 2H), 1.62-1.48 (m, 1H), 1.25 (s, 3H).

1. additionAfter addition
2. stirringThe reaction mixture was stirred at ˜0° C. for 1.5 hrs
3. customThe reaction was quenched with water
4. extractionthe resulting mixture (pH>10) was extracted with EtOAc (3×)
5. washThe combined organic phase was washed with water (2×), saturated aqueous NaCl (2×)
6. dry with materialdried over Na2SO4
7. filtrationfiltered
8. concentrationconcentrated
9. customThe crude product was crystallized from EtOAc

ORD record

ord-115f8e5ece1f470683678777cdf91663

Source dataset

uspto-grants-2014_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08710049B2