Acetyl chloride → Methyl 2-methylbenzo[d]oxazole-6-carboxylate

HRID 2080000Notes

Reaction equation

HRID 2080000 reaction equation
[CH3:1][O:2][C:3](=[O:12])[C:4]1[CH:9]=[CH:8][C:7]([NH2:10])=[C:6]([OH:11])[CH:5]=1.[C:13](Cl)(=O)[CH3:14].C1(C)C=CC(S([O-])(=O)=O)=CC=1.[NH+]1C=CC=CC=1.C(N(CC)CC)C>C1(C)C(C)=CC=CC=1.C(OCC)(=O)C>[CH3:1][O:2][C:3]([C:4]1[CH:9]=[CH:8][C:7]2[N:10]=[C:13]([CH3:14])[O:11][C:6]=2[CH:5]=1)=[O:12]

Participants

7

Reactant 4

HCID 6367Acetyl chlorideHCID 8471TriethylamineHCID 466102Benzenesulfonic acid, 4-methyl-, compd. with pyridine (1:1)HCID 7020619Benzoic acid, 4-amino-3-hydroxy-, methyl ester

Product 1

HCID 12157467Methyl 2-methylbenzo[d]oxazole-6-carboxylateYield 80.4%

Reagents, catalysts & solvents 2

HCID 7237O-XyleneSolventHCID 8857Ethyl AcetateSolvent

Procedure

To a solution of 4-amino-3-hydroxy-benzoic acid methyl ester (2085 mg, 12.47 mmmol) in xylene (200 mL) were added acetyl chloride (1.06 mL, 14.96 mmol), pyridinium p-toluenesulfonate (940 mg, 3.74 mmol) and triethylamine (2.09 mL, 14.96 mmol), and the solution was stirred for 8.5 hours under reflux. Ethyl acetate was added to the reaction mixture, which was then washed with water, dried over anhydrous magnesium sulfate, then, evaporated in vacuo, the resulting residue was purified by silica gel chromatography (hexane-ethyl acetate), and the title compound (1917 mg, 10.02 mmol, 80.4%) was obtained.

Workup

  1. temperatureunder reflux
  2. washwas then washed with water
  3. dry with materialdried over anhydrous magnesium sulfate
  4. customevaporated in vacuo
  5. customthe resulting residue was purified by silica gel chromatography (hexane-ethyl acetate)

Sources & evidence

ORD record
ord-a560d48824da4beeafc684cda17f42ef
Source dataset
uspto-grants-2011_04
Patent number
US07932272B2

Reaction notes

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