Ethylamine → N-Ethyl-3-nitro PABA

HRID 1591968Notes

Reaction equation

HRID 1591968 reaction equation
F[C:2]1[CH:10]=[CH:9][C:5]([C:6]([OH:8])=[O:7])=[CH:4][C:3]=1[N+:11]([O-:13])=[O:12].[CH2:14]([NH2:16])[CH3:15]>CO>[CH2:14]([NH:16][C:2]1[CH:10]=[CH:9][C:5]([C:6]([OH:8])=[O:7])=[CH:4][C:3]=1[N+:11]([O-:13])=[O:12])[CH3:15]

Participants

4

Reactant 2

HCID 6341EthylamineHCID 679874-Fluoro-3-nitrobenzoic acid

Product 1

HCID 3729086N-Ethyl-3-nitro PABA

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Conditions

Temperature
75 °C

Procedure

To a suspension of 1.85 g of 4-fluoro-3-nitrobenzoic acid (10 mmol) in 25 mL of MeOH is added 20 mL of ethylamine (2.0M in THF). The resulting yellow solution is stirred at 75° C. for 5 h then at RT for 48 h. The solvent is removed under reduced pressure, then water is added to the residue. The resulting orange suspension is acidified with 2N aqueous HCl and the yellow precipitate is collected by filtration, washed with water and dried in vacuo to give 4-ethylamino-3-nitro-benzoic acid: mp=233-236° C.; 1H-NMR (DMSO-d6) δ 12.83 (s, 1H), 8.61 (d, J=1.84, 1H), 8.49 (m, 1H), 7.97 (dd, 1H), 7.12 (d, J=9.2, 1H), 3.46 (m, 2H), 1.23 (t, 3H); [M−1]−=209.

Workup

  1. waitat RT for 48 h
  2. customThe solvent is removed under reduced pressure
  3. additionwater is added to the residue
  4. filtrationthe yellow precipitate is collected by filtration
  5. washwashed with water
  6. customdried in vacuo

Sources & evidence

ORD record
ord-5df5124fc50746d2b05e96d8c798951b
Source dataset
uspto-grants-2007_11
Patent number
US07291635B2

Reaction notes

Loading…