Benzenepropanal → 2,3-dihydro-6-fluoro-2-(2-phenylethyl)-4H-1-benzopyran-4-one

HRID 2248292Notes

Reaction equation

HRID 2248292 reaction equation
N1CCCC1.[OH:6][C:7]1[CH:12]=[CH:11][C:10]([F:13])=[CH:9][C:8]=1[C:14](=[O:16])[CH3:15].[C:17]1([CH2:23][CH2:24][CH:25]=O)[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=1>C1(C)C=CC=CC=1.C(OCC)(=O)C>[F:13][C:10]1[CH:11]=[CH:12][C:7]2[O:6][CH:25]([CH2:24][CH2:23][C:17]3[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=3)[CH2:15][C:14](=[O:16])[C:8]=2[CH:9]=1

Participants

6

Reactant 3

HCID 7707BenzenepropanalHCID 31268PyrrolidineHCID 959922-Acetyl-4-fluorophenol

Product 1

HCID 190944442,3-dihydro-6-fluoro-2-(2-phenylethyl)-4H-1-benzopyran-4-one

Reagents, catalysts & solvents 2

HCID 1140TolueneSolventHCID 8857Ethyl AcetateSolvent

Procedure

Pyrrolidine (2.4 mL) was added to a solution of 2'-hydroxy-5'-fluoroacetophenone (15.1 g) and 3-phenylpropanal (13.2 mL) in toluene (30 mL), and the mixture heated under reflux in a Dean-Stark apparatus for 3 hours, cooled, diluted with ethyl acetate and washed with aqueous 1N HCl, aqueous 1N NaOH, H2O, brine, dried (Na2SO4), filtered and evaporated, and the residue purified by column chromatography (6:1 hexane/diethyl ether, SiO2) to yield 2,3-dihydro-6-fluoro-2-(2-phenylethyl)-4H-1-benzopyran-4-one (18 gm, Rf=0.3 4:1 hexane/diethyl ether).

Workup

  1. temperaturethe mixture heated
  2. temperatureunder reflux in a Dean-Stark apparatus for 3 hours
  3. temperaturecooled
  4. washwashed with aqueous 1N HCl, aqueous 1N NaOH, H2O, brine
  5. dry with materialdried (Na2SO4)
  6. filtrationfiltered
  7. customevaporated
  8. customthe residue purified by column chromatography (6:1 hexane/diethyl ether, SiO2)

Sources & evidence

ORD record
ord-25b3ed20483046c3a088aa1d99281986
Source dataset
uspto-grants-1991_08
Patent number
US05039672

Reaction notes

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