1,2,4-Trifluoro-5-nitrobenzene → N-Ethyl-4,5-difluoro-2-nitrobenzenamine

HRID 1048990Notes

Reaction equation

HRID 1048990 reaction equation
[F:1][C:2]1[CH:7]=[C:6]([N+:8]([O-:10])=[O:9])[C:5](F)=[CH:4][C:3]=1[F:12].[CH3:13][CH2:14][N:15](C(C)C)C(C)C.[Si](OCCN)(C(C)(C)C)(C)C>C(#N)C>[CH2:14]([NH:15][C:5]1[CH:4]=[C:3]([F:12])[C:2]([F:1])=[CH:7][C:6]=1[N+:8]([O-:10])=[O:9])[CH3:13]

Participants

5

Reactant 3

HCID 750121,2,4-Trifluoro-5-nitrobenzeneHCID 81531DiisopropylethylamineHCID 529218(2-Aminoethoxy)(tert-butyl)dimethylsilane

Product 1

HCID 58110957N-Ethyl-4,5-difluoro-2-nitrobenzenamine

Reagents, catalysts & solvents 1

HCID 6342AcetonitrileSolvent

Procedure

To a stirred solution of 1,2,4-trifluoro-5-nitrobenzene (0.5 g, 0.0028 mol) in acetonitrile (5 ml) was added DIPEA (0.98 ml, 0.0056 mol) and 2-(tert-butyldimethylsilyloxy)ethanamine (0.49 g, 0.0028 mol) was added portion wise under cooling condition with constant stirring. The reaction mixture was allowed to stir at room temperature for 4 h. The reaction was concentrated and diluted with water (20 ml) and extracted with ethyl acetate (3×25 ml). The combined organic layers were washed with brine dried over Na2SO4 and concentrated in vacuo and purified by column chromatography on silica gel to afford the desired product N-ethyl-4,5-difluoro-2-nitroaniline. (37 as yellow solid. 1H NMR (400 MHz, DMSO-d6) δ: 8.37 (bs, 1H), 8.13-8.17 (dd, J=8.4, 8.4 Hz, 1H), 7.21-7.27 (dd, J=7.2, 7.2 Hz, 1H), 3.8-3.82 (t, J=5.2 Hz, 2H) 3.45-3.49 (m, 2H), 0.84 (s, 9H), 0.021 (s, 6H). MS (M+1=333).

Workup

  1. additionwas added portion wise
  2. temperatureunder cooling condition with constant stirring
  3. concentrationThe reaction was concentrated
  4. additiondiluted with water (20 ml)
  5. extractionextracted with ethyl acetate (3×25 ml)
  6. washThe combined organic layers were washed with brine
  7. dry with materialdried over Na2SO4
  8. concentrationconcentrated in vacuo
  9. custompurified by column chromatography on silica gel

Sources & evidence

ORD record
ord-1b539c2027a24a38bc5f9db2290bf8a9
Source dataset
uspto-grants-2016_07
Patent number
US09382226B2

Reaction notes

Loading…