Triethylamine → 4-Bromo-7-(2,2-dimethyl-propionyloxy)-2-phenyl-oxazolo[4,5-c]pyridine-6-carboxylic acid methyl ester

HRID 2388143Notes

Reaction equation

HRID 2388143 reaction equation
[CH3:1][O:2][C:3]([C:5]1[N:10]=[C:9]([Br:11])[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][C:23]([CH3:28])([CH3:27])[C:24](Cl)=[O:25].C(N(CC)CC)C>CN(C)C1C=CN=CC=1.C(Cl)Cl.C(OCC)(=O)C>[CH3:1][O:2][C:3]([C:5]1[N:10]=[C:9]([Br:11])[C:8]2[N:12]=[C:13]([C:15]3[CH:16]=[CH:17][CH:18]=[CH:19][CH:20]=3)[O:14][C:7]=2[C:6]=1[O:21][C:24](=[O:25])[C:23]([CH3:28])([CH3:27])[CH3:22])=[O:4]

Participants

7

Reactant 3

HCID 8471TriethylamineHCID 62493Pivaloyl chlorideHCID 866481114-Bromo-7-hydroxy-2-phenyl-oxazolo[4,5-c]pyridine-6-carboxylic acid methyl ester

Product 1

HCID 866481124-Bromo-7-(2,2-dimethyl-propionyloxy)-2-phenyl-oxazolo[4,5-c]pyridine-6-carboxylic acid methyl esterYield 41.2%

Reagents, catalysts & solvents 3

HCID 142844-(Dimethylamino)pyridineCatalystHCID 6344DichloromethaneSolventHCID 8857Ethyl AcetateSolvent

Procedure

A solution of 4-bromo-7-hydroxy-2-phenyl-oxazolo[4,5-c]pyridine-6-carboxylic acid methyl ester (0.1 g, 0.286 mmol; example 3a), trimethylacetyl chloride (42.3 μL, 0.344 mmol), triethylamine (79.7 μL, 0.572 mmol), and 4-(dimethylamino)pyridine (3.5 mg, 0.03 mmol) in methylene chloride (2.5 mL) was stirred at room temperature for 2 hours. The reaction mixture was diluted with ethyl acetate and washed with saturated sodium bicarbonate solution, brine, saturated ammonium chloride solution, and brine. The organic fraction was dried over anhydrous sodium sulfate, and concentrated. The crude product was purified by flash chromatography eluting from silica gel with a gradient of 0-70% ethyl acetate in hexanes to give 51 mg of the title compound as a white solid. MS: (+) m/z 432.8, 434.8 (M+1, 79Br/81Br).

Workup

  1. washwashed with saturated sodium bicarbonate solution, brine, saturated ammonium chloride solution, and brine
  2. dry with materialThe organic fraction was dried over anhydrous sodium sulfate
  3. concentrationconcentrated
  4. customThe crude product was purified by flash chromatography
  5. washeluting from silica gel with a gradient of 0-70% ethyl acetate in hexanes

Sources & evidence

ORD record
ord-4b193b5b530b4bdc93e9dedfdb63965f
Source dataset
uspto-grants-2012_09
Patent number
US08269008B2

Reaction notes

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