3-(4-Fluorophenyl)-2-methylpropanoic acid → 6-Fluoro-2-methylindan-1-one

HRID 263633Notes

Reaction equation

HRID 263633 reaction equation
[F:1][C:2]1[CH:13]=[CH:12][C:5]([CH2:6][CH:7]([CH3:11])[C:8]([OH:10])=O)=[CH:4][CH:3]=1>O>[F:1][C:2]1[CH:3]=[C:4]2[C:5]([CH2:6][CH:7]([CH3:11])[C:8]2=[O:10])=[CH:12][CH:13]=1

Participants

3

Reactant 1

HCID 154877913-(4-Fluorophenyl)-2-methylpropanoic acid

Product 1

HCID 114465226-Fluoro-2-methylindan-1-one

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Conditions

Temperature
95 °C

Procedure

To 932 g. polyphosphoric acid at 70° on the steam bath is added ρ-fluoro-a-methylhydrocinnamic acid (93.2 g., 0.5 mole) slowly with stirring. The temperature is gradually raised to 95° C., and the mixture kept at this temperature for 1 hour. The mixture is allowed to cool and added to 2 l. of water. The aqueous layer is extracted with ether, the ether solution washed twice with saturated sodium chloride solution, 5% Na2CO3 solution, water, and then dried. The ether filtrate is concentrated with 200 g. silica-gel, and added to a five pound silica-gel column packed with 5% ether-petroleum ether. The column is eluted with 5-10% ether-petroleum ether and followed by TLC to give 6-fluoro-2-methylindanone.

Workup

  1. temperatureto cool
  2. additionadded to 2 l
  3. extractionThe aqueous layer is extracted with ether
  4. washthe ether solution washed twice with saturated sodium chloride solution, 5% Na2CO3 solution, water
  5. customdried
  6. concentrationThe ether filtrate is concentrated with 200 g
  7. additionsilica-gel, and added to a five pound silica-gel column
  8. washThe column is eluted with 5-10% ether-petroleum ether

Sources & evidence

ORD record
ord-ffb5190070144d5cbbd52ed2463a2983
Source dataset
uspto-grants-1997_07
Patent number
US05643959

Reaction notes

Loading…