4-(6-Nitropyridin-3-yl)-3-oxopiperazine-1-carboxylic acid tert-butyl ester → Tert-butyl 4-(6-aminopyridin-3-yl)-3-oxopiperazine-1-carboxylate

HRID 1772140Notes

Reaction equation

HRID 1772140 reaction equation
[N+:1]([C:4]1[N:9]=[CH:8][C:7]([N:10]2[CH2:15][CH2:14][N:13]([C:16]([O:18][C:19]([CH3:22])([CH3:21])[CH3:20])=[O:17])[CH2:12][C:11]2=[O:23])=[CH:6][CH:5]=1)([O-])=O>C(O)C>[NH2:1][C:4]1[N:9]=[CH:8][C:7]([N:10]2[CH2:15][CH2:14][N:13]([C:16]([O:18][C:19]([CH3:21])([CH3:20])[CH3:22])=[O:17])[CH2:12][C:11]2=[O:23])=[CH:6][CH:5]=1

Participants

3

Reactant 1

HCID 592909524-(6-Nitropyridin-3-yl)-3-oxopiperazine-1-carboxylic acid tert-butyl ester

Product 1

HCID 59290959Tert-butyl 4-(6-aminopyridin-3-yl)-3-oxopiperazine-1-carboxylateYield 95%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

A 250-mL Parr reactor bottle was purged with nitrogen and charged with 10% palladium on carbon (50% wet, 100 mg dry weight) and a solution of 121a (500 mg, 1.55 mmol) in ethanol (20 mL). The bottle was attached to Parr hydrogenator, evacuated, charged with hydrogen gas to a pressure of 45 psi and shaken for 4 h. After this time, the hydrogen was evacuated, and nitrogen was charged into the bottle. Celite 521 (1.0 g) was added, and the mixture was filtered through a pad of Celite 521. The filter cake was washed with ethanol (2×30 mL), and the filtrate was concentrated under reduced pressure to afford a 95% yield of 121b (430 mg) as an amber film: 1H NMR (500 MHz, CDCl3) δ 7.98 (d, 1H, J=2.5 Hz), 7.38 (dd, 1H, J=8.5, 2.0 Hz), 6.52 (d, 1H, J=8.5 Hz), 4.54 (s, 1H), 4.26 (s, 2H), 3.78 (t, 2H, J=5.5 Hz), 3.67 (t, 2H, J=5.0 Hz), 1.50 (s, 9H); MS (ESI+) m/z 293.1 (M+H).

Workup

  1. customA 250-mL Parr reactor bottle was purged with nitrogen
  2. additioncharged with 10% palladium on carbon (50% wet, 100 mg dry weight)
  3. customevacuated
  4. additioncharged with hydrogen gas to a pressure of 45 psi
  5. customAfter this time, the hydrogen was evacuated
  6. additionnitrogen was charged into the bottle
  7. additionCelite 521 (1.0 g) was added
  8. filtrationthe mixture was filtered through a pad of Celite 521
  9. washThe filter cake was washed with ethanol (2×30 mL)
  10. concentrationthe filtrate was concentrated under reduced pressure

Sources & evidence

ORD record
ord-6ff0a5bfd0814f63a4bec6bb439be25f
Source dataset
uspto-grants-2016_02
Patent number
US09249123B2

Reaction notes

Loading…