Reaktion #561418

Reaktionsgleichung

2-chloro-5-nitrophenol

cesium carbonate

tert-butyl 3-bromopropylcarbamate

→

tert-butyl 3-(2-chloro-5-nitrophenoxy)propylcarbamate

Ausbeute 57.4%

Lösungsmittel

DMF

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeThe solvent was removed under reduced pressure
2. 2
   Waschenwashed with brine (2×200 mL)
3. 3
   TrocknenThe organic layer was dried over anhydrous sodium sulphate
4. 4
   Einengenconcentrated under reduced pressure

Vorschrift

To a stirred solution of 2-chloro-5-nitrophenol (2 g, 11.62 mmol), cesium carbonate (5.66 g, 17.44 mmol) in DMF (20 mL) was added tert-butyl 3-bromopropylcarbamate (4.13 g, 17.44 mmol) followed by tetrabutylammonium iodide (0.214 g, 0.581 mmol) at room temperature. The reaction mixture was stirred at room temperature for 18 h while monitoring by TLC and LC-MS. The solvent was removed under reduced pressure and the residue was taken up in ethyl acetate (200 mL) and washed with brine (2×200 mL). The organic layer was dried over anhydrous sodium sulphate and concentrated under reduced pressure to give tert-butyl 3-(2-chloro-5-nitrophenoxy)propylcarbamate (2.2 g, 57.4%) as a light-brown solid. LC-MS (M−100)+=230.7 1H NMR (400 MHz, CDCl3) δ ppm 7.82-7.76 (2H, m), 7.52 (1H, d, J=8.4 Hz), 4.99 (1H, s), 4.20 (2H, t, J=5.6 Hz), 3.41-3.37 (2H, q, J=6.0 Hz), 2.12-2.01 (2H, m), 1.43 (9H, s).

Quelle