N-bromobutanimide → Methyl 2-(bromomethyl)-3-cyanobenzoate

HRID 1993752Notes

Reaction equation

HRID 1993752 reaction equation
[C:1]([C:3]1[C:4]([CH3:13])=[C:5]([CH:10]=[CH:11][CH:12]=1)[C:6]([O:8][CH3:9])=[O:7])#[N:2].C1C(=O)N([Br:21])C(=O)C1>ClC(Cl)(Cl)Cl.C1C=CC=CC=1.C(OOC(=O)C1C=CC=CC=1)(=O)C1C=CC=CC=1.N(C(C)(C)C#N)=NC(C)(C)C#N>[Br:21][CH2:13][C:4]1[C:3]([C:1]#[N:2])=[CH:12][CH:11]=[CH:10][C:5]=1[C:6]([O:8][CH3:9])=[O:7]

Participants

7

Reactant 2

HCID 67184N-bromobutanimide2×HCID 13170186Methyl 3-cyano-2-methylbenzoate

Product 1

HCID 17837598Methyl 2-(bromomethyl)-3-cyanobenzoateYield 98.2%

Reagents, catalysts & solvents 4

HCID 6547AzobisisobutyronitrileCatalystHCID 7187Benzoyl PeroxideCatalystHCID 241BenzeneSolventHCID 5943Carbon TetrachlorideSolvent

Procedure

A suspension of methyl 3-cyano-2-methylbenzoate (10.6 g, 60.5 mmol), NBS (16.2 g, 90.7 mmol) and azobisisobutyronitrile (AIBN) (100 mg) in tetrachloromethane (200 mL) was refluxed under nitrogen atmosphere for 6 hours. Alternatively, the bromination step was carried out using NBS in benzene, using benzoyl peroxide as a catalyst. TLC analysis showed the complete consumption of methyl 3-cyano-2-methylbenzoate (TLC solvent: 10% ethyl acetate in hexane). The reaction mixture was filtered and washed with chloroform (3×20 mL). The combined filtrate and washings were concentrated under reduced pressure. The residue was washed through a short column of silica gel using 10% ethyl acetate in hexanes as an eluent. The eluent was concentrated and the resultant product dried under vacuum overnight to provide 15.1 g of methyl 2-bromomethyl-3-cyanobenzoate (98% yield). 1H NMR spectrum (in DMSO-d6): δ 8.15, (d, J=8.0 Hz, 1H); 8.12 (d, J=7.9 Hz, 1H); 7.67 (t, 1H); 5.04 (s, 2H); 3.89 (s, 3H).

Workup

  1. temperaturewas refluxed under nitrogen atmosphere for 6 hours
  2. customthe complete consumption of methyl 3-cyano-2-methylbenzoate (TLC solvent: 10% ethyl acetate in hexane)
  3. filtrationThe reaction mixture was filtered
  4. washwashed with chloroform (3×20 mL)
  5. concentrationThe combined filtrate and washings were concentrated under reduced pressure
  6. washThe residue was washed through a short column of silica gel using 10% ethyl acetate in hexanes as an eluent
  7. concentrationThe eluent was concentrated
  8. dry with materialthe resultant product dried under vacuum overnight

Sources & evidence

ORD record
ord-c6a0392d5c8742b7903fe1b712f84e89
Source dataset
uspto-grants-2010_01
Patent number
US07652028B2

Reaction notes

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