Reaktion #40870

Reaktionsgleichung

p-toluenesulphonate

L-valine

diisopropylethylamine

bromide

1,1,1,3,3,3-hexamethyldisilazane

→

N-(4-bromobenzyl)-L-valine

Ausbeute 89.0%

Lösungsmittel

CH2Cl2

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturheated
2. 2
   Temperaturat reflux
3. 3
   SonstigeWhen all the 4-bromobenzylo bromide has been consumed
4. 4
   Sonstigethe solvent is evaporated off at low pressure, 100 mL of water
5. 5
   workup.ADDITIONis added and after 1 h at 0° C. the solid
6. 6
   Filtrationis filtered
7. 7
   Sonstigedried in an air oven at 40° C.

Vorschrift

To a suspension of 10 g (34.6 mmol) of p-toluenesulphonate of L-valine in 100 mL of CH2Cl2 is added at 20-25° C. and under nitrogen atmosphere 8.0 mL (38 mmol) of 1,1,1,3,3,3-hexamethyldisilazane. After shaking the mixture at 20-25° C. for one hour, 13.2 mL (76 mmol) of diisopropylethylamine and 8.64 g (34.6 mmol) of 4-bromobenzylo bromide are added and heated at reflux. When all the 4-bromobenzylo bromide has been consumed, the solvent is evaporated off at low pressure, 100 mL of water is added and after 1 h at 0° C. the solid is filtered and dried in an air oven at 40° C. to provide 8.8 g (89%) of N-(4-bromobenzyl)-L-valine.

Quelle