Tetrahydrofuran → Ethyl 2-hydroxy-4-methyl-2-(trifluoromethyl)pent-4-enoate

HRID 400614

Reaction equation

HRID 400614 reaction equation
[F:1][C:2]([F:11])([F:10])[C:3](=[O:9])[C:4]([O:6][CH2:7][CH3:8])=[O:5].C[CH:13]=[CH:14][CH2:15][Mg]Cl.[CH2:18]1COCC1>>[CH2:7]([O:6][C:4](=[O:5])[C:3]([OH:9])([C:2]([F:10])([F:11])[F:1])[CH2:18][C:14]([CH3:15])=[CH2:13])[CH3:8]

Participants

4

Reactant 3

HCID 8028TetrahydrofuranHCID 2737239Ethyl 3,3,3-trifluoro-2-oxopropanoateHCID 178448201HCID 178448201, compound

Product 1

HCID 17935595Ethyl 2-hydroxy-4-methyl-2-(trifluoromethyl)pent-4-enoateYield 60%

Procedure

A solution of ethyl trifluoropyruvate (124.84 g, 0.734 mol) in 2.0 L of THF was treated with methylallyl magnesium chloride (0.5 M in THF, 1.90 L, 0.954 mol) over 4 hours while the internal temperature was maintained below −60° C. The reaction mixture was allowed to reach room temperature overnight, concentrated in vacuo to remove THF, quenched with 1 L of saturated ammonium chloride solution, and extracted with three 1 L portions of diethyl ether. The combined organic phases were washed with 100 mL of brine, dried over magnesium sulfate, filtered, and concentrated in vacuo. Vacuum distillation at 60 mmHg afforded 100.1 g of 2-hydroxy-4-methyl-2-trifluoromethylpent-4-enoic acid ethyl ester as a clear oil (b.p. 97° C.-103° C., 60% yield).

Workup

  1. temperaturewas maintained below −60° C
  2. concentrationconcentrated in vacuo
  3. customto remove THF
  4. customquenched with 1 L of saturated ammonium chloride solution
  5. extractionextracted with three 1 L portions of diethyl ether
  6. washThe combined organic phases were washed with 100 mL of brine
  7. dry with materialdried over magnesium sulfate
  8. filtrationfiltered
  9. concentrationconcentrated in vacuo
  10. distillationVacuum distillation at 60 mmHg

Sources & evidence

ORD record
ord-55fc4eac33794c92a6f65f23fa972c41
Source dataset
uspto-grants-2014_06
Patent number
US08741897B2

Linked notes

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