N-bromobutanimide → Methyl 4-(bromomethyl)-3-nitrobenzoate

HRID 1987355Notes

Reaction equation

HRID 1987355 reaction equation
[CH3:1][O:2][C:3](=[O:14])[C:4]1[CH:9]=[CH:8][C:7]([CH3:10])=[C:6]([N+:11]([O-:13])=[O:12])[CH:5]=1.[Br:15]N1C(=O)CCC1=O.N(C1(C#N)CCCCC1)=NC1(C#N)CCCCC1>C(Cl)(Cl)(Cl)Cl>[CH3:1][O:2][C:3](=[O:14])[C:4]1[CH:9]=[CH:8][C:7]([CH2:10][Br:15])=[C:6]([N+:11]([O-:13])=[O:12])[CH:5]=1

Participants

5

Reactant 3

HCID 67184N-bromobutanimideHCID 749781,1'-Azobis(cyclohexanecarbonitrile)HCID 81816Methyl 4-methyl-3-nitrobenzoate

Product 1

HCID 13399987Methyl 4-(bromomethyl)-3-nitrobenzoateYield 61%

Reagents, catalysts & solvents 1

HCID 5943Carbon TetrachlorideSolvent

Procedure

To a solution of 4-methyl-3-nitrobenzoic acid (5.52 g, 30.5 mmol) in MeOH (100 mL) was added 98% sulfuric acid (2 mL) and the resultant mixture was refluxed overnight, then cooled to room temperature. The mixture was concentrated and the residue was dissolved in CH2Cl2 (50 mL) and water (20 mL). Solid Na2CO3 was added until the aqueous phase was basic to litmus paper. The phases were separated and the aqueous phase was extracted with CH2Cl2 (5×20 mL). The combined organic extracts were dried (Na2SO4) and concentrated and provided 5.79 g (97%) of 4-methyl-3-nitrobenzoic acid methyl ester as a white solid. To a solution of 4-methyl-3-nitrobenzoic acid methyl ester (5.01 g, 25.7 mmol) in CCl4 (65 mL) was added N-bromosuccinimide (5.04 g, 28.3 mmol) followed by 1,1′-azobis(cyclohexanecarbonitrile) (1.21 g, 4.96 mmol). The resultant mixture was refluxed for 24 hours then cooled to room temperature, filtered through filter paper, and concentrated. Purification of the crude material by column chromatography on silica gel (9:1 :hexanes-EtOAc) provided 4.30 g (61%) of 4-bromomethyl-3-nitrobenzoic acid methyl ester as a yellow oil. 1H NMR (CDCl3) δ 3.98 (s, 3H), 4.85 (s, 2H), 7.67 (d, 1H, J=7.8 Hz), 8.25 (d, 1H, J=7.8, 1.5 Hz), 8.66 (d, 1H, J=1.5 Hz).

Workup

  1. filtrationfiltered
  2. filtrationthrough filter paper
  3. concentrationconcentrated
  4. customPurification of the crude material by column chromatography on silica gel (9:1 :hexanes-EtOAc)

Sources & evidence

ORD record
ord-323749061d5d46b9b053bd44d3872eec
Source dataset
uspto-grants-2009_06
Patent number
US07550484B2

Reaction notes

Loading…