Tetramethyltin → 7-Hydroxy-4-methyl-2-phenyl-oxazolo[4,5-c]pyridine-6-carboxylic acid methyl ester

HRID 2388138Notes

Reaction equation

HRID 2388138 reaction equation
[CH3:1][O:2][C:3]([C:5]1[N:10]=[C:9](Br)[C:8]2[N:12]=[C:13]([C:15]3[CH:20]=[CH:19][CH:18]=[CH:17][CH:16]=3)[O:14][C:7]=2[C:6]=1[OH:21])=[O:4].[CH3:22][Sn](C)(C)C>CN(C)C=O.C(OCC)(=O)C.Cl[Pd](Cl)([P](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1)[P](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1>[CH3:1][O:2][C:3]([C:5]1[N:10]=[C:9]([CH3:22])[C:8]2[N:12]=[C:13]([C:15]3[CH:20]=[CH:19][CH:18]=[CH:17][CH:16]=3)[O:14][C:7]=2[C:6]=1[OH:21])=[O:4]

Participants

6

Reactant 2

HCID 11661TetramethyltinHCID 866481114-Bromo-7-hydroxy-2-phenyl-oxazolo[4,5-c]pyridine-6-carboxylic acid methyl ester

Product 1

HCID 675293807-Hydroxy-4-methyl-2-phenyl-oxazolo[4,5-c]pyridine-6-carboxylic acid methyl esterYield 61.1%

Reagents, catalysts & solvents 3

HCID 178418476HCID 178418476, compoundCatalystHCID 6228DimethylformamideSolventHCID 8857Ethyl AcetateSolvent

Conditions

Temperature
130 °C

Procedure

Under a nitrogen atmosphere, a mixture of 4-bromo-7-hydroxy-2-phenyl-oxazolo[4,5-c]pyridine-6-carboxylic acid methyl ester (200 mg, 0.573 mmol), tetramethyltin (0.32 mL, 2.29 mmol), and dichlorobis(triphenylphosphine)palladium(II) (40.2 mg, 0.057 mmol) was suspended in 4.8 mL of anhydrous N,N-dimethylformamide. The reaction mixture was heated at 130° C. for 1 hour, cooled to room temperature, and diluted with ethyl acetate. The organic mixture was successively washed with saturated sodium bicarbonate solution, brine, saturated ammonium chloride solution, and brine. The organic phase was dried over anhydrous sodium sulfate and concentrated. The residue was purified by flash chromatography eluting from silica gel with a gradient of 0-100% ethyl acetate in hexanes to give 99.6 mg of the title compound as a white solid. MS: (+) m/z 285.0 (M+1).

Workup

  1. temperaturecooled to room temperature
  2. washThe organic mixture was successively washed with saturated sodium bicarbonate solution, brine, saturated ammonium chloride solution, and brine
  3. dry with materialThe organic phase was dried over anhydrous sodium sulfate
  4. concentrationconcentrated
  5. customThe residue was purified by flash chromatography
  6. washeluting from silica gel with a gradient of 0-100% ethyl acetate in hexanes

Sources & evidence

ORD record
ord-0d709158ec014dd1bfd78c68e7aa9291
Source dataset
uspto-grants-2012_09
Patent number
US08269008B2

Reaction notes

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