Reaktion #161983

Reaktionsgleichung

#@5

(3R,4S,5S)-4-[{N-[(9H-fluoren-9-ylmethoxy)carbonyl]-L-valyl}(methyl)amino]-3-methoxy-5-methylheptanoic acid

pyridine

pentafluorophenyl trifluoroacetate

→

#174

Ausbeute 92.2%

pentafluorophenyl (3R,4S,5S)-4-[{N-[(9H-fluoren-9-ylmethoxy)carbonyl]-L-valyl}(methyl)amino]-3-methoxy-5-methylheptanoate

Ausbeute 92.2%

Lösungsmittel

dichloromethane

Reaktionsbedingungen

Aufarbeitung

1. 1
   EinengenThe reaction was concentrated in vacuo
2. 2
   Sonstigepurified by silica gel chromatography (Gradient: 0 to 52% ethyl acetate in heptane)

Vorschrift

To a solution of #@5 (19.43 g, 37.03 mmol, 1 eq.) in dichloromethane (100 mL) and pyridine (5.86 g, 74.1 mmol, 2 eq.) was added pentafluorophenyl trifluoroacetate (20.7 g, 74.1 mmol, 2 eq.) and the reaction was stirred at room temperature for 1 hour. The reaction was concentrated in vacuo and purified by silica gel chromatography (Gradient: 0 to 52% ethyl acetate in heptane) to afford #174 (23.58 g, 92%) as a yellow oil. LC-MS (Protocol Q1): m/z 691.2 [M+H+], retention time=1.23 minutes.

Quelle