Isobutyric Acid → 2,2-Dimethylhexanoic Acid

HRID 1706038Notes

Reaction equation

HRID 1706038 reaction equation
[CH:1](NC(C)C)([CH3:3])[CH3:2].[CH2:8]([Li])CCC.[C:13]([OH:18])(=[O:17])[CH:14]([CH3:16])[CH3:15].ICCCC>C1COCC1.CCCCCC>[CH3:15][C:14]([CH3:8])([CH2:16][CH2:2][CH2:1][CH3:3])[C:13]([OH:18])=[O:17]

Participants

7

Reactant 4

HCID 6590Isobutyric AcidHCID 7912DiisopropylamineHCID 10962Butyl iodideHCID 178418339Butyllithium

Product 1

HCID 1632172,2-Dimethylhexanoic Acid

Reagents, catalysts & solvents 2

HCID 8028TetrahydrofuranSolvent2×HCID 8058HexaneSolvent

Procedure

A solution of 102 g (1.02 mol) of diisopropylamine (distilled from calcium hydride) in 730 ml of dry THF was stirred under argon in an ice-bath as a full bottle (1.0 mol) of solution of n-butyllithium in hexane (Alpha, 2.4 M, ca. 417 ml) was added dropwise at a rate such that the temperature held below 8°. About halfway through the addition, the ice-bath was replaced by an ice-methanol bath to better control the temperature at 0° C. throughout the rest of the addition. The resultant mixture was kept in the cold bath and stirred for 15 minutes before a 41.6 g (0.427 mol) portion of isobutyric acid was added dropwise, again keeping the temperature below 0°. Final portions of the acid were rinsed into the reaction mixture with several ml of dry THF. After another 15 minutes a 57 ml (0.499 mol) portion of 1-iodo-butane was added dropwise. After the addition was completed, the ice-bath was removed and the resultant mixture was stirred for 2 hours. The ice-bath was used again as the resultant mixture was quenched by the dropwise addition of a solution of 200 ml of concentrated hydrochloric acid in 640 ml of water. The phases were separated and the aqueous phase was back-extracted with ether. The combined extract was washed with aqueous sodium bisulfite, dried (MgSO4) and evaporated in vacuo. The residue was distilled at 20 mm to yield 56.8 g of XXIX as an oil, bp 110°-113°; nmr 0.90 (3, broad t, J=5.7 Hz), 1.18 (6, s) and 1.0-2.0 (6, m).

Workup

  1. additionwas added dropwise at a rate such that the temperature
  2. customheld below 8°
  3. additionAbout halfway through the addition
  4. additionthe temperature at 0° C. throughout the rest of the addition
  5. additionwas added dropwise
  6. customthe temperature below 0°
  7. additionAfter the addition
  8. customthe ice-bath was removed
  9. customwas quenched by the dropwise addition of a solution of 200 ml of concentrated hydrochloric acid in 640 ml of water
  10. customThe phases were separated
  11. extractionthe aqueous phase was back-extracted with ether
  12. extractionThe combined extract
  13. washwas washed with aqueous sodium bisulfite
  14. dry with materialdried (MgSO4)
  15. customevaporated in vacuo
  16. distillationThe residue was distilled at 20 mm

Sources & evidence

ORD record
ord-931b9e41adb54613bc904b31cf1e1637
Source dataset
uspto-grants-1980_06
Patent number
US04206127

Reaction notes

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