Triethylamine → Tert-butyl 3-methyl-1-oxobutan-2-ylcarbamate

HRID 659135Notes

Reaction equation

HRID 659135 reaction equation
[OH:1][CH2:2][CH:3]([NH:7][C:8](=[O:14])[O:9][C:10]([CH3:13])([CH3:12])[CH3:11])[CH:4]([CH3:6])[CH3:5].C(N(CC)CC)C>CS(C)=O>[CH3:5][CH:4]([CH3:6])[CH:3]([NH:7][C:8](=[O:14])[O:9][C:10]([CH3:13])([CH3:12])[CH3:11])[CH:2]=[O:1]

Participants

4

Reactant 2

HCID 8471TriethylamineHCID 545981N-Boc-DL-valinol2×

Product 1

HCID 545985Tert-butyl 3-methyl-1-oxobutan-2-ylcarbamateYield 72.1%

Reagents, catalysts & solvents 1

HCID 679Dimethyl SulfoxideSolvent2×

Conditions

Temperature
0 °C

Procedure

To a solution of 1.75 g of tert-butyl 1-hydroxy-3-methylbutan-2-ylcarbamate (Formula 20) in 25 mL of DMSO was added 3.6 mL of triethylamine. The solution was cooled to 0° C. and 4.1 grams of sulfur trioxide pyridine complex in 25 mL of DMSO was added. The reaction mixture was stirred at room temperature for 1 hour. Then, the mixture was poured onto ice-water and extracted with ethyl acetate. The organic layers were washed with 10% acetic acid, water, 5% sodium bicarbonate, and brine, dried over sodium sulfate and concentrated. Column chromatography (30% ethyl acetate/hexane) gave 1.25 g of tert-butyl 3-methyl-1-oxobutan-2-ylcarbamate (Formula 21) as a clear oil. 1H NMR (300 MHz, CDCl3) δ 0.95 (d, J=7.32 Hz, 3H), 1.03 (d, J=6.83 Hz, 3H), 1.45 (s, 9H), 2.27-2.29 (m, 1H), 4.24-4.26 (m, 1H), 9.65 (s, 1H).

Workup

  1. additionThen, the mixture was poured onto ice-water
  2. extractionextracted with ethyl acetate
  3. washThe organic layers were washed with 10% acetic acid, water, 5% sodium bicarbonate, and brine
  4. dry with materialdried over sodium sulfate
  5. concentrationconcentrated

Sources & evidence

ORD record
ord-58746b33dbe24035af15d1c504d049a3
Source dataset
uspto-grants-2011_12
Patent number
US08080570B2

Reaction notes

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