tert-butyl 7-nitro-3,4-dihydroquinoline-1(2H)-carboxylate → tert-Butyl 7-amino-3,4-dihydroquinoline-1(2H)-carboxylate

HRID 2404763Notes

Reaction equation

HRID 2404763 reaction equation
[C:1]([O:5][C:6]([N:8]1[C:17]2[C:12](=[CH:13][CH:14]=[C:15]([N+:18]([O-])=O)[CH:16]=2)[CH2:11][CH2:10][CH2:9]1)=[O:7])([CH3:4])([CH3:3])[CH3:2]>CO.[Pd]>[NH2:18][C:15]1[CH:16]=[C:17]2[C:12]([CH2:11][CH2:10][CH2:9][N:8]2[C:6]([O:5][C:1]([CH3:4])([CH3:3])[CH3:2])=[O:7])=[CH:13][CH:14]=1

Participants

4

Reactant 1

HCID 57470252tert-butyl 7-nitro-3,4-dihydroquinoline-1(2H)-carboxylate

Product 1

HCID 44558562tert-Butyl 7-amino-3,4-dihydroquinoline-1(2H)-carboxylate

Reagents, catalysts & solvents 2

HCID 23938PalladiumCatalystHCID 887MethanolSolvent

Procedure

A suspension of the crude 7-nitro-3,4-dihydro-2H-quinoline-1-carboxylic acid tert-butyl ester (4.5 g, 16.2 mol) and 10% Pd—C (0.45 g) in MeOH (40 mL) was stirred under H2 (1 atm) at room temperature overnight. After filtration, the filtrate was concentrated and the residue was purified by column chromatography (petroleum ether-EtOAc, 5:1) to give tert-butyl 7-amino-3,4-dihydroquinoline-1(2H)-carboxylate (DC-1) as a brown solid (1.2 g, 22% over 2 steps). 1H NMR (CDCl3) δ 7.15 (d, J=2 Hz, 1H), 6.84 (d, J=8 Hz, 1H), 6.36-6.38 (m, 1H), 3.65-3.68 (m, 2H), 3.10 (br s, 2H), 2.66 (t, J=6.4 Hz, 2H), 1.84-1.90 (m, 2H), 1.52 (s, 9H); ESI-MS 496.8 m/z (2M+H+).

Workup

  1. filtrationAfter filtration
  2. concentrationthe filtrate was concentrated
  3. customthe residue was purified by column chromatography (petroleum ether-EtOAc, 5:1)

Sources & evidence

ORD record
ord-7d4cbf98bc0c4c4e9824c1f97cc8d09b
Source dataset
uspto-grants-2014_08
Patent number
US08802700B2

Reaction notes

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