Reaction #1683

Reaction equation

trifluoroacetic acid

Boc-D-Phe-Pro-OBn

anisole

→

white powder

Yield 85.0%

D-Phe-Pro-OBn.TFA

Yield 85.0%

Solvents

dichloromethane

Conditions

Workup

1. 1
   Otherthe solvents were evaporated in vacuo
2. 2
   workup.DISSOLUTIONthe thick oily residue was dissolved in diethyl ether (1.5 L)
3. 3
   Other(72 hours)
4. 4
   FiltrationThe white precipitate was filtered
5. 5
   Washwashed with diethyl ether (300 mL)
6. 6
   Otherdried

Procedure

To a stirring solution of Boc-D-Phe-Pro-OBn (68 g, 150 mmol) in dichloromethane (50 mL) at 0° C., was added anisole (20 mL) followed by trifluoroacetic acid (400 mL). After stirring for 3 hours, the solvents were evaporated in vacuo and the thick oily residue was dissolved in diethyl ether (1.5 L) and refrigerated (72 hours). The white precipitate was filtered, washed with diethyl ether (300 mL) and dried to yield 59.4 g (85%) of white powder.

Source