tert-Butanol → Tert-butyl 2-methylbutanoate

HRID 1880326Notes

Reaction equation

HRID 1880326 reaction equation
[C:1]([OH:5])([CH3:4])([CH3:3])[CH3:2].CCN(CC)CC.[CH3:13][CH:14]([CH2:18][CH3:19])[C:15](Cl)=[O:16]>CN(C1C=CN=CC=1)C.C(Cl)Cl>[C:1]([O:5][C:15](=[O:16])[CH:14]([CH3:13])[CH2:18][CH3:19])([CH3:4])([CH3:3])[CH3:2]

Participants

6

Reactant 3

HCID 6386tert-ButanolHCID 8471TriethylamineHCID 93697Butanoyl chloride, 2-methyl-

Product 1

HCID 523483Tert-butyl 2-methylbutanoate

Reagents, catalysts & solvents 2

HCID 142844-(Dimethylamino)pyridineCatalystHCID 6344DichloromethaneSolvent

Conditions

Temperature
0 °C

Procedure

To a solution of t-butyl alcohol (40.7 g, 549 mmol), Et3N (70 mL, 505 mmol), and DMAP (0.366 mL, 3 mmol) in anhydrous CH2Cl2 (100 mL) at 0° C. was added 2-methyl-butyryl chloride (38 g from step 1). The reaction was stirred at 0° C. for 2 h and then room temperature overnight. The cloudy reaction mixture was filtered through celite and concentrated. The residue was diluted with Et2O and washed with 0.1 N HCl. The organic layer was dried (MgSO4), filtered, and concentrated. The residue was distillated at ˜100° C. bath temperature under weak in-house vacuum twice to give the desired 2-methyl-butyric acid tert-butyl ester 2-2 as a clear oil (42 g, ˜85% purity by 1HNMR analysis). 1HNMR (CDCl3, 500 Hz): 2.28-2.20 (m 1H), 1.68-1.56 (m, 1H), 1.44 (s, 9H), 1.46-1.37 (m, 1H), 1.44 (s, 9H), 1.09 (d, J=7.0 hz, 3H), 0.9 (t, J=7.3 Hz, 3H).

Workup

  1. customroom temperature overnight
  2. customThe cloudy reaction mixture
  3. filtrationwas filtered through celite
  4. concentrationconcentrated
  5. additionThe residue was diluted with Et2O
  6. washwashed with 0.1 N HCl
  7. dry with materialThe organic layer was dried (MgSO4)
  8. filtrationfiltered
  9. concentrationconcentrated
  10. customwas distillated at ˜100° C.

Sources & evidence

ORD record
ord-8bf073097adf4775b51151e75fb3bfb2
Source dataset
uspto-grants-2012_11
Patent number
US08318764B2

Reaction notes

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