Methanol → 2-Trifluoroacetyl-1-tetralone

HRID 1274291Notes

Reaction equation

HRID 1274291 reaction equation
[F:1][C:2]([F:9])([F:8])[C:3]([O:5]CC)=O.C[O-].[Na+].CO.[C:15]1(=[O:25])[C:24]2[C:19](=[CH:20][CH:21]=[CH:22][CH:23]=2)[CH2:18][CH2:17][CH2:16]1>CCOCC.Cl>[F:9][C:2]([F:1])([F:8])[C:3]([CH:16]1[CH2:17][CH2:18][C:19]2[C:24](=[CH:23][CH:22]=[CH:21][CH:20]=2)[C:15]1=[O:25])=[O:5]

Participants

7

Reactant 4

HCID 887MethanolHCID 9794Ethyl trifluoroacetateHCID 107241-TetraloneHCID 10942334Sodium Methoxide

Product 1

HCID 69171222-Trifluoroacetyl-1-tetraloneYield 81%

Reagents, catalysts & solvents 2

HCID 313Hydrochloric AcidSolventHCID 3283Diethyl EtherSolvent2×

Procedure

A 250 mL one necked round bottomed flask equipped with a reflux condenser, nitrogen inlet and provisions for magnetic stirring was charged with ethyl trifluoroacetate (28.4 g, 0.2 mol) and 75 mL of ether. To this solution was added 48 mL of 25% sodium methoxide in methanol (0.21 mol). A solution of 1-tetralone (29.2 g, 0.2 mol) in 50 mL of ether was added over about 5 minutes. The reaction mixture was stirred at room temperature for 14 hours and was diluted with 100 mL of 3N HCl. The phases were separated and the organic layer was washed with 3N HCl, and with brine, dried over anhydrous MgSO4, filtered and concentrated in vacuo. The residue was taken up in 70 mL of boiling ethanol/water and cooled to room temperature, whereupon crystals of 2-trifluoroacetyl-1-tetralone formed which were isolated by filtration and air dried to give pure compound (32 g, 81%): mp 48-49° C.; 1H NMR CDCl3 δ 2.8 (m, 2H), 2.9 (m, 2H), 7.2 (d, j=3.0 Hz, 1H), 7.36 (m, 1H), 7.50 (m, 1H), 7.98 (m, 1H); 19F NMR CDCl3 δ -72.0. EI GC-MS M+=242.

Workup

  1. stirringThe reaction mixture was stirred at room temperature for 14 hours
  2. customThe phases were separated
  3. washthe organic layer was washed with 3N HCl
  4. dry with materialwith brine, dried over anhydrous MgSO4
  5. filtrationfiltered
  6. concentrationconcentrated in vacuo
  7. customformed which
  8. customwere isolated by filtration and air
  9. customdried

Sources & evidence

ORD record
ord-36ccfceece52467bb9f5198e0304882b
Source dataset
uspto-grants-2000_12
Patent number
US06156781

Reaction notes

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