Hydrochloric Acid → 2-Methyl-5-nitrobenzoyl chloride

HRID 2165876Notes

Reaction equation

HRID 2165876 reaction equation
Cl.[CH3:2][C:3]1[CH:11]=[CH:10][C:9]([N+:12]([O-:14])=[O:13])=[CH:8][C:4]=1[C:5](O)=[O:6].S(Cl)([Cl:17])=O>>[CH3:2][C:3]1[CH:11]=[CH:10][C:9]([N+:12]([O-:14])=[O:13])=[CH:8][C:4]=1[C:5]([Cl:17])=[O:6]

Participants

4

Reactant 3

HCID 313Hydrochloric AcidHCID 24386Thionyl ChlorideHCID 5196832-Methyl-5-nitrobenzoic acid

Product 1

HCID 44365682-Methyl-5-nitrobenzoyl chloride

Procedure

Part A. A 1-L flask equipped with a reflux condenser and a nitrogen sweep to an HCl gas scrubber was charged with 2-methyl-5-nitrobenzoic acid (200 g, 1.10 mol). The reaction vessel was cooled in an ice bath and thionyl chloride (307 mL, 4.20 mol) was added in one portion. The ice bath was removed, and the reaction mixture was refluxed overnight. The excess thionyl chloride and the SO2 and HCl reaction side-products were removed by vacuum distillation to afford 2-methyl-5-nitrobenzoyl chloride as a solid residue, which was used without further purification. This material was immediately dissolved in methylene chloride (100 mL) and added dropwise with stirring to a commercial 40% dimethylamine solution (500 mL, 4.45 mol) which was maintained at 0° to 12° by periodic immersion in a dry ice-acetone bath. After complete addition, the reaction mixture was stirred for 30 minutes at room temperature. The reaction mixture was diluted with water and extracted with methylene chloride. The combined organic extracts were washed with water, dried, and concentrated. The resulting material was distilled under vacuum to afford 5-nitro-N,N,2-trimethylbenzamide (189.9 g, 0.91 mol, 83% yield) as a solid: mp 98°-99°; bp 156°-170° (0.5 torr); MS m/e 209(M+ +H); 1H NMR(CDCl3) δ 8.00-8.17(m,2H), 7.40(d,J=8 Hz,1H), 3.17(s,3H), 2.88 (s,3H), 2.41(s,3H). Anal. Calcd for C10H12N2O3 : C,57.69; H,5.81; N,13.45. Found: C,57.72; H,5.84; N,13.49.

Workup

  1. customA 1-L flask equipped with a reflux condenser
  2. temperatureThe reaction vessel was cooled in an ice bath
  3. customThe ice bath was removed
  4. temperaturethe reaction mixture was refluxed overnight
  5. customThe excess thionyl chloride and the SO2 and HCl reaction side-products
  6. customwere removed by vacuum distillation

Sources & evidence

ORD record
ord-987c4f91a5534a92945f27de4906cb04
Source dataset
uspto-grants-1990_07
Patent number
US04942163

Reaction notes

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