7-(4-Fluorophenyl)-5-oxo-5,7-dihydrofuro[3,4-b]pyridine → Phenyl(pyridin-2-yl)methanol
Reaction equation
F[C:2]1[CH:7]=[CH:6][C:5]([CH:8]2[C:12]3=[N:13][CH:14]=[CH:15][CH:16]=[C:11]3C(=O)[O:9]2)=[CH:4][CH:3]=1>[OH-].[Na+]>[N:13]1[CH:14]=[CH:15][CH:16]=[CH:11][C:12]=1[CH:8]([C:5]1[CH:4]=[CH:3][CH:2]=[CH:7][CH:6]=1)[OH:9]Participants
Reactant 1
Product 1
Reagents, catalysts & solvents 1
Conditions
- Temperature
- 75 °C
Procedure
A suspension of 7-(4-fluorophenyl)-5-oxo-5,7-dihydrofuro[3,4-b]pyridine (2.93 g, 12.79 mmol) in 64 ml of 0.2N NaOH is heated to 75° C. with stirring for 24 hours. The mixture is then filtered and the filtrate evaporated to produce crude 2-pyridyl phenyl carbinol, which is not further purified, but rather, dissolved in 70 mL of pyridine and treated with chromium (VI) oxide pyridine complex (10.0 g, 38.78 mmol). A black mixture results which is stirred at 23° C. for 24 hours, then treated with saturated aqueous NaHCO3 (50 ml) and extracted with CHCl3 (3×75 mL). Acidification of the basic aqueous layer to pH 2 with concentrated HCl generates a precipitate which is filtered and dried to produce crude 2-(4-fluorobenzoyl)pyridine-3-carboxylic acid. Treatment of the latter with diazomethane in ether, followed by silica gel chromotography of the resulting solid (using hexane-EtOAc (3:1) as the eluent) produces 3 -carbomethoxy-2-(4-fluorobenzoyl)pyridine. M.P. 95°-96.5° C.
Workup
- filtrationThe mixture is then filtered
- customthe filtrate evaporated
Sources & evidence
- ORD record
- ord-f3ca341996d54222bf215a06ca78c486
- Source dataset
- uspto-grants-1989_02
- Patent number
- US04806535
Reaction notes
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