Tetrahydrofuran → tert-butyl (S)-2-methylhexanoate

HRID 1510984Notes

Reaction equation

HRID 1510984 reaction equation
FC(F)(F)S(O[C@@H:7]([CH3:15])[C:8]([O:10][C:11]([CH3:14])([CH3:13])[CH3:12])=[O:9])(=O)=O.[CH2:18]([Mg]Cl)[CH2:19][CH2:20]C.[Cl-].[NH4+].O1CCC[CH2:27]1>[Cl-].[Zn+2].[Cl-].O>[CH3:27][C@@H:7]([CH2:15][CH2:18][CH2:19][CH3:20])[C:8]([O:10][C:11]([CH3:14])([CH3:13])[CH3:12])=[O:9]

Participants

7

Reactant 4

HCID 8028TetrahydrofuranHCID 25517Ammonium ChlorideHCID 11780840(S)-2-(Trifluoromethylsulfonyloxy)propionic acid tert-butyl esterHCID 178418265HCID 178418265, compound

Product 1

HCID 25259677tert-butyl (S)-2-methylhexanoate

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 3007855ZincchlorideSolvent

Conditions

Temperature
0 °C

Procedure

In a 10 ml Schlenk tube, 3.5 mg of dry zinc chloride was dissolved in 3.0 ml of absolute tetrahydrofuran and cooled to 0° C. under argon. Thereafter, 279 mg of tert-butyl (S)-2-trifluoromethanesulphonyloxypropionate (ee>99%) and 0.700 ml of n-butylmagnesium chloride (2.00 M solution in THF) were added in succession and the reaction was stirred for 3 h at 0° C. Thereafter, the reaction mixture was diluted with petroleum ether, first water and then saturated ammonium chloride solution were added and the organic phase was separated off. This was applied directly to a silica gel filter and washed with petroleum ether. The product was then washed off with a petroleum ether/diethyl ether mixture (10:1) from the filter and freed from the solvent. The pure tert-butyl (S)-2-methylhexanoate (entry 3 in table 1)(ee>99%) was obtained in quantitative yield.

Workup

  1. customthe organic phase was separated off
  2. filtrationfilter
  3. washwashed with petroleum ether
  4. washThe product was then washed off with a petroleum ether/diethyl ether mixture (10:1) from the
  5. filtrationfilter

Sources & evidence

ORD record
ord-f912b677ab8a4368828dbf6b396a2317
Source dataset
uspto-grants-2012_07
Patent number
US08212065B2

Reaction notes

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