Hydrochloric Acid → 2-Phenyl-3-pyridinol

HRID 1939893Notes

Reaction equation

HRID 1939893 reaction equation
Br[C:2]1[C:7]([OH:8])=[CH:6][CH:5]=[CH:4][N:3]=1.[C:9]1(B(O)O)[CH:14]=[CH:13][CH:12]=[CH:11][CH:10]=1.Cl>C1(C)C=CC=CC=1.C(O)C.[OH-].[Na+].O>[OH:8][C:7]1[C:2]([C:9]2[CH:14]=[CH:13][CH:12]=[CH:11][CH:10]=2)=[N:3][CH:4]=[CH:5][CH:6]=1

Participants

8

Reactant 3

HCID 313Hydrochloric AcidHCID 230702-Bromo-3-pyridinolHCID 66827Phenylboronic Acid

Product 1

HCID 187052-Phenyl-3-pyridinolYield 45.4%

Reagents, catalysts & solvents 4

HCID 702EthanolSolventHCID 962WaterSolventHCID 1140TolueneSolventHCID 14798Sodium HydroxideSolvent

Conditions

Temperature
100 °C

Procedure

A mixture of 2-bromo-3-hydroxypyridine (2.20 g, 12.6 mmol), phenylboronic acid (2.00 g, 16.3 mmol) and palladium (tetrakis)triphenylphosphine (250 mg) in toluene (30 mL), ethanol (15 mL) and 5% aqueous sodium hydroxide (15 mL) was degassed with a stream of nitrogen and stirred vigorously at 100° C. overnight. The mixture was diluted with water (50 mL) and ethylacetate (100 mL), and the organic layer was dried over sodium sulfate and concentrated, affording a yellow solid. This material was suspended in water (100 mL), a few mL of 1N HCl was added, and the resulting solution was extracted with ethylacetate. The aqueous layer was neutralized with saturated aqueous sodium bicarbonate, and again was extracted with ethylacetate. The combined organic extracts were dried with sodium sulfate and concentrated to an oily solid, which was triturated with 2:1 hexane/ethylacetate, affording 0.98 g of 3-hydroxy-2-phenylpyridine.

Workup

  1. customwas degassed with a stream of nitrogen
  2. additionThe mixture was diluted with water (50 mL) and ethylacetate (100 mL)
  3. dry with materialthe organic layer was dried over sodium sulfate
  4. concentrationconcentrated
  5. customaffording a yellow solid
  6. extractionthe resulting solution was extracted with ethylacetate
  7. extractionagain was extracted with ethylacetate
  8. dry with materialThe combined organic extracts were dried with sodium sulfate
  9. concentrationconcentrated to an oily solid, which
  10. customwas triturated with 2:1 hexane/ethylacetate

Sources & evidence

ORD record
ord-fedbdf620e024226beb8479010f540e6
Source dataset
uspto-grants-1997_12
Patent number
US05698547

Reaction notes

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