Reaktion #1483095

Reaktionsgleichung

pTSA

DL-valine

1-dodecanol

→

Dodecyl 2-amino-3-methylbutanoate

Lösungsmittel

toluene

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONAfter addition
2. 2
   Temperaturthe temperature of the reaction mixture was slowly raised
3. 3
   Temperaturto reflux temperature
4. 4
   Sonstigethe water was separated azeotropically
5. 5
   EinengenThe reaction mixture was concentrated under vacuum
6. 6
   Waschenwashed with aqueous 5% Na2CO3 (3×50 mL)
7. 7
   TrocknenThe organic layer was dried over Na2SO4
8. 8
   Einengenconcentrated under vacuum
9. 9
   Sonstigeto afford
10. 10
    Sonstigecrude 35 (40 g, yield, 82%) as a liquid

Vorschrift

To a stirred solution of DL-valine 34 (20 g, 170.7 mmol) in toluene (200 mL) was added 1-dodecanol 2 (28.6 g, 153 mmol) in one lot, followed by pTSA (35.7 g, 187.7 mmol). After addition, the temperature of the reaction mixture was slowly raised to reflux temperature and the water was separated azeotropically. The reaction mixture was monitored by TLC. The reaction mixture was concentrated under vacuum. The obtained residue was taken in ethyl acetate (200 mL) and washed with aqueous 5% Na2CO3 (3×50 mL) followed by brine solution. The organic layer was dried over Na2SO4 and concentrated under vacuum to afford crude 35 (40 g, yield, 82%) as a liquid.

Quelle