Réaction #11338

Équation de réaction

N-(t-butoxycarbonyl)-N-benzyl-L-phenylalaninol

TEMPO

sodium bromide

sodium bicarbonate

→

N-(t-Butoxycarbonyl)-N-benzyl-L-phenylalaninal

Rendement 100.3%

Solvants

toluene

water

ethyl acetate

Conditions de réaction

Traitement

1. 1
   workup.ADDITIONwas added slowly over 30 minutes
2. 2
   workup.ADDITIONThree more additions (0.4 mL each) of bleach was added
3. 3
   workup.STIRRINGby stirring for 10 minutes
4. 4
   workup.ADDITIONafter each addition
5. 5
   Autreto consume all the stating material
6. 6
   Autreto separate
7. 7
   ExtractionThe aqueous layer was extracted twice with 8 mL of toluene
8. 8
   LavageThe combined organic layer was washed with 1.25 mL of a solution
9. 9
   workup.ADDITIONcontaining 0.075 g of potassium iodide, sodium bisulfate(0.125 g) and water (1.1 mL), 1.25 mL of 10% aqueous sodium thiosulfate solution, 1.25 mL of pH 7 phosphate buffer and 1.5 mL of brine solution
10. 10
    SéchageThe organic solution was dried over magnesium sulfate
11. 11
    Filtrationfiltered
12. 12
    Concentrationconcentrated under reduced pressure

Mode opératoire

To a solution of 0.32 g (0.94 mmoles) of N-(t-butoxycarbonyl)-N-benzyl-L-phenylalaninol in 2.8 mL of toluene was added 2.4 mg (0.015 mmoles) of 2,2,6,6-tetramethyl-1-piperidinyloxy, free radical (TEMPO), 0.1 g (0.97 mmoles) of sodium bromide, 2.8 mL of ethyl acetate and 0.34 mL of water. The mixture was cooled to 0° C. and an aqueous solution of 4.2 mL of 5% household bleach containing 0.23 g (3.0 mL, 2.738 mmoles) of sodium bicarbonate was added slowly over 30 minutes. The mixture was stirred at 0° C. for 10 minutes. Three more additions (0.4 mL each) of bleach was added followed by stirring for 10 minutes after each addition to consume all the stating material. The two phase mixture was allowed to separate. The aqueous layer was extracted twice with 8 mL of toluene. The combined organic layer was washed with 1.25 mL of a solution containing 0.075 g of potassium iodide, sodium bisulfate(0.125 g) and water (1.1 mL), 1.25 mL of 10% aqueous sodium thiosulfate solution, 1.25 mL of pH 7 phosphate buffer and 1.5 mL of brine solution. The organic solution was dried over magnesium sulfate, filtered and concentrated under reduced pressure to give 0.32 g (100% yield) of N-(t-Butoxycarbonyl)-N-benzyl-L-phenylalaninal.

Source