Reaction #1483096

Reaction equation

pTSA

DL-phenylalanine

dodecanol 2

→

39

Yield 99.1%

Dodecyl 2-amino-3-phenylpropanoate

Yield 99.1%

Solvents

toluene

Conditions

Workup

1. 1
   TemperatureThe temperature of the reaction mixture was slowly raised
2. 2
   Temperatureto reflux temperature
3. 3
   Otherthe water was separated azeotropically The reaction mixture
4. 4
   ConcentrationThe reaction mixture was concentrated under vacuum
5. 5
   Washwashed with aqueous 5% Na2CO3 (3×50 mL)
6. 6
   DryingThe organic layer was dried over Na2SO4
7. 7
   Concentrationconcentrated under vacuum

Procedure

To a stirred solution of DL-phenylalanine 38 (5 g, 30.26 mmol) in toluene (100 mL) was added dodecanol 2 (5.08 g, 27.24 mmol) in one lot, followed by pTSA (6.33 g, 33.29 mmol). 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 39 (9 g, yield: 89.1%) as a liquid.

Source