p-Toluenesulfonic acid → HCID 22677350, compound

HRID 1837450Notes

Reaction equation

HRID 1837450 reaction equation
O[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][C:3]=1[NH:8][C:9]([C:11]1[CH:16]=[C:15]([NH2:17])[C:14]([Cl:18])=[C:13]([Cl:19])[N:12]=1)=[O:10].C1(C)C=CC(S(O)(=O)=O)=CC=1>C1(C)C=CC=CC=1.C(OCC)(=O)C.C1COCC1>[NH2:17][C:15]1[CH:16]=[C:11]([C:9]2[O:10][C:2]3[CH:7]=[CH:6][CH:5]=[CH:4][C:3]=3[N:8]=2)[N:12]=[C:13]([Cl:19])[C:14]=1[Cl:18]

Participants

6

Reactant 2

HCID 6101p-Toluenesulfonic acidHCID 22677309HCID 22677309, compound

Product 1

HCID 22677350HCID 22677350, compoundYield 80.7%

Reagents, catalysts & solvents 3

HCID 1140TolueneSolventHCID 8028TetrahydrofuranSolventHCID 8857Ethyl AcetateSolvent

Procedure

A solution of N-(2-hydroxyphenyl)-4-amino-5,6-dichloropyridine-2-carboxamide (1.80 g, 5.7 mmol) (obtained from N-(2-hydroxyphenyl)-2-(4,5,6-trichloro)pyridinecarboxamide via azide formation followed by sodium borohydride reduction) and p-toluenesulfonic acid (0.2 g) in toluene (50 mL) was refluxed overnight under nitrogen with a Dean-Stark trap. After cooling, the reaction mixture was diluted with ethyl acetate and THF, and the organic mixture washed with saturated aqueous sodium bicarbonate. The organic layer was dried, concentrated, and the residue triturated with petroleum ether/diethyl ether to provide 4-amino-2,3-dichloro-6-(2-benzoxazolyl)pyridine (1.30 g, 4.6 mmol). 1H NMR (DMSO-d6): δ 7.82 (d, 2H), 7.66 (s, 1H), 7.55-7.38 (m, 2H), 7.18 (br.s, 2H).

Workup

  1. temperatureAfter cooling
  2. washthe organic mixture washed with saturated aqueous sodium bicarbonate
  3. customThe organic layer was dried
  4. concentrationconcentrated
  5. customthe residue triturated with petroleum ether/diethyl ether

Sources & evidence

ORD record
ord-3957f4d91f734545b4aa88c9cfa28805
Source dataset
uspto-grants-2004_08
Patent number
US06784137B2

Reaction notes

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