Reaktion #325977

Reaktionsgleichung

3-phenyl-2,2-bis(3-(trifluoromethoxy)phenyl)propanoic acid

triethylamine

diphenylphosphoryl azide

trimethylsilylethanol

EtOAc

→

2-(trimethylsilyl)ethyl 2-phenyl-1,1-bis(3-(trifluoromethoxy)phenyl)ethylcarbamate

Ausbeute 54.0%

Lösungsmittel

1,4-dioxane

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturheated at 75° C. for 1.5 h
2. 2
   SonstigeThe cooled reaction mixture
3. 3
   Filtrationfiltered through celite
4. 4
   EinengenThe filtrate was concentrated under reduced pressure
5. 5
   Sonstigepurified by ISCO silica gel chromatography

Vorschrift

To a solution of 3-phenyl-2,2-bis(3-(trifluoromethoxy)phenyl)propanoic acid (0.055 g, 0.117 mmol) in 1,4-dioxane (2 mL) was added triethylamine (0.014 g, 20 μL, 0.14 mmol), 4 Å molecular sieves (0.05 g), diphenylphosphoryl azide (0.040 g, 31 μL, 0.14 mmol) and trimethylsilylethanol (0.042 g, 50 μL, 0.35 mmol). The reaction mixture was stirred for 1 h at rt, then heated at 75° C. for 1.5 h. The cooled reaction mixture was diluted with EtOAc and filtered through celite. The filtrate was concentrated under reduced pressure and purified by ISCO silica gel chromatography using a gradient of 0-20% EtOAc/hexane as eluent to yield 2-(trimethylsilyl)ethyl 2-phenyl-1,1-bis(3-(trifluoromethoxy)phenyl)ethylcarbamate (Example 282) as a colorless band (0.037 g, 54% yield). HPLC: RT=4.828 min (Phenomenex Luna C18 5μ column 4.6×50 mm, eluting with 10-90% MeOH/H2O containing 0.1% PPA over a 4 minute gradient, monitoring at 220 nm). No molecular ion was obtained. 1H NMR (400 MHz, CDCl3): 7.32 (t, J=8.1 Hz, 2H), 7.18-7.11 (m, 7H), 6.99 (s, 2H), 6.65 (d, J=7.1 Hz, 2H), 5.35 (s, 1H), 4.08 (t, J=8.8 Hz, 2H), 3.78 (s, 2H), 0.88 (br, 2H), 0.00 (s, 9H).

Quelle