Reaction #3349

Reaction equation

toluene

2[2-[2-(1-tert-butoxycarbonyl-3-methyl-butylcarbamoyl)-5-methoxyphenyldisulfanyl]-4-methoxybenzoylamino]-4-methyl-pentanoic acid tert-butyl ester

anisole

trifluoroacetic acid

→

title compound

Yield 69.5%

2-[2-[2-(1-Carboxy-3-methylbutylcarbamoyl)-5-methoxy-phenyldisulfanyl]-4-methoxybenzoylamino]-4-methyl-pentanoic acid

Yield 69.5%

Solvents

dichloromethane

Conditions

Workup

1. 1
   Otherthe solvents were removed in vacuo
2. 2
   OtherThe crude product was recrystallized from methanol/water

Procedure

A solution of [S-(R*,R*)-2[2-[2-(1-tert-butoxycarbonyl-3-methyl-butylcarbamoyl)-5-methoxyphenyldisulfanyl]-4-methoxybenzoylamino]-4-methyl-pentanoic acid tert-butyl ester (1.2 g, 1.7 mmol) and anisole (1 mL) in 10 mL dichloromethane, cooled to about 0° C., was treated dropwise with 10 mL of trifluoroacetic acid. The mixture was allowed to warm to ambient temperature. After 4 hours, 5 mL toluene was added, and the solvents were removed in vacuo. The crude product was recrystallized from methanol/water to yield 0.7 g of the title compound.

Source