Acetone → 2-(4-(Trifluoromethyl)phenyl)-2-propanol

HRID 726137Notes

Reaction equation

HRID 726137 reaction equation
[Mg].BrCCBr.Br[C:7]1[CH:12]=[CH:11][C:10]([C:13]([F:16])([F:15])[F:14])=[CH:9][CH:8]=1.[CH3:17][C:18]([CH3:20])=[O:19]>C1COCC1>[F:14][C:13]([F:16])([F:15])[C:10]1[CH:11]=[CH:12][C:7]([C:18]([OH:19])([CH3:20])[CH3:17])=[CH:8][CH:9]=1

Participants

6

Reactant 4

HCID 180AcetoneHCID 78391,2-DibromoethaneHCID 67872Benzene, 1-bromo-4-(trifluoromethyl)-HCID 5462224Magnesium

Product 1

HCID 27776172-(4-(Trifluoromethyl)phenyl)-2-propanol

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent2×

Procedure

To magnesium turnings (30.2 g, 1.24 mol) in THF (30 mL) is added 1,2-dibromoethane (0.7 mL) followed by dropwise addition, over 1 h, of 4-bromotrifluoromethylbenzene (200 g, 0.89 mol) dissolved in THF (700 mL). The reaction is heated occasionally to maintain a gentle reflux and is stirred 45 min after the addition is complete. The dark reaction mixture is then cooled in an ice bath and acetone (103 g, 1.78 mol) added dropwise. After stirring an additional 1.5 h the reaction is carefully quenched with aqueous saturated NaHSO4, ethyl acetate added, the organics dried over MgSO4, concentrated and purified by silica gel chromatography (9:1 to 3:2, hexane to ethyl acetate) to give 4-trifluoromethyl-α,α-dimethylbenzyl alcohol of sufficient purity to carry to the next step; yield: 114 g (63%).

Workup

  1. temperatureThe reaction is heated occasionally
  2. temperatureto maintain
  3. temperaturea gentle reflux
  4. additionafter the addition
  5. customThe dark reaction mixture
  6. temperatureis then cooled in an ice bath
  7. stirringAfter stirring an additional 1.5 h the reaction
  8. customis carefully quenched with aqueous saturated NaHSO4, ethyl acetate
  9. additionadded
  10. dry with materialthe organics dried over MgSO4
  11. concentrationconcentrated
  12. custompurified by silica gel chromatography (9:1 to 3:2, hexane to ethyl acetate)

Sources & evidence

ORD record
ord-d7850aedff7f4fd38e4a1ac26b557118
Source dataset
uspto-grants-1998_01
Patent number
US05708001

Reaction notes

Loading…