Potassium Carbonate → 4-Methoxy-3-(2-methylbenzoxazol-5-yl)benzenecarboxaldehyde

HRID 2113103Notes

Reaction equation

HRID 2113103 reaction equation
[CH:1]([C:3]1[CH:4]=[CH:5][C:6]([O:12][CH3:13])=[C:7](B(O)O)[CH:8]=1)=[O:2].[CH3:14][C:15]1[O:16][C:17]2[CH:23]=[CH:22][C:21](Br)=[CH:20][C:18]=2[N:19]=1.C([O-])([O-])=O.[K+].[K+]>C(O)C.C1(C)C=CC=CC=1>[CH3:13][O:12][C:6]1[CH:5]=[CH:4][C:3]([CH:1]=[O:2])=[CH:8][C:7]=1[C:21]1[CH:22]=[CH:23][C:17]2[O:16][C:15]([CH3:14])=[N:19][C:18]=2[CH:20]=1

Participants

6

Reactant 3

HCID 11430Potassium CarbonateHCID 27343675-Formyl-2-methoxyphenylboronic acidHCID 101045995-Bromo-2-methyl-1,3-benzoxazole

Product 1

HCID 223915884-Methoxy-3-(2-methylbenzoxazol-5-yl)benzenecarboxaldehydeYield 89.6%

Reagents, catalysts & solvents 2

HCID 702EthanolSolventHCID 1140TolueneSolvent

Procedure

A solution of 5-formyl-2-methoxybenzeneboronic acid (1 g, 5.6 mmol), 2-methyl-5-bromobenzoxazole (1 g, 4.72 mmol) and K2CO3 (1.63 g, 11.8 mmol) in ethanol (20 mL) and toluene (40 mL) was degassed prior to addition of Pd(Ph3)4 (55 mg, 0.047 mmol). The mixture was refluxed for 20 hours then cooled and filtered through diatomaceous earth. The filtrate was concentrated in vacuo, extracted with ethyl acetate, washed with water and the organic layer dried over sodium sulphate. The crude was purified by column chromatography (heptane/ethyl acetate 7/3 to 6/4) to give 1.13 g of title compound.

Workup

  1. temperatureThe mixture was refluxed for 20 hours
  2. temperaturethen cooled
  3. filtrationfiltered through diatomaceous earth
  4. concentrationThe filtrate was concentrated in vacuo
  5. extractionextracted with ethyl acetate
  6. washwashed with water
  7. dry with materialthe organic layer dried over sodium sulphate
  8. customThe crude was purified by column chromatography (heptane/ethyl acetate 7/3 to 6/4)

Sources & evidence

ORD record
ord-55582cdeb74343e8b1b2d61a40ee8e12
Source dataset
uspto-grants-2009_04
Patent number
US07524873B2

Reaction notes

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