Reaktion #77210

Reaktionsgleichung

4-bromo-benzoic acid ethyl ester

diethyl phosphite

→

oil

Ausbeute 67.9%

4-(Diethoxyphosphoryl)-benzoic Acid Ethyl Ester

Ausbeute 67.9%

Lösungsmittel

acetonitrile

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeA sealed pressure flask, flushed with N2
2. 2
   workup.ADDITIONcontaining
3. 3
   Temperaturheated at 90° C. for 18 hours
4. 4
   FiltrationThe reaction mixture was filtered through celite
5. 5
   Waschenthe celite was washed with EtOAc (3×30 mL) until the filtrate
6. 6
   TrocknenThe combined organics were dried over Na2SO4
7. 7
   Einengenconcentrated on a rotary evaporator
8. 8
   SonstigeThe desired product was purified by silica gel flash chromatography

Vorschrift

A sealed pressure flask, flushed with N2, containing a mixture of 4-bromo-benzoic acid ethyl ester (2a) (5 g, 0.0218 mol), diethyl phosphite (3.093 mL, 0.024 mol), NMM (2.88 mL, 0.0262 mmol) and Pd(PPh3)4 (2.017 g, 0.00175 mol) in acetonitrile (20 mL) was stirred at ambient temperature for 5-10 min, then heated at 90° C. for 18 hours. The reaction mixture was filtered through celite, and the celite was washed with EtOAc (3×30 mL) until the filtrate showed little or no evidence of product by HPLC. The combined organics were dried over Na2SO4 and concentrated on a rotary evaporator. The desired product was purified by silica gel flash chromatography to give a pale yellow oil (4.24 g). 1H NMR (300 MHz, CDCl3) δ (ppm)) 1.36 (m, 6H), 1.42 (t, J=7 Hz, 3H), 4.16 (m, 4H), 4.42 (q, J=7 Hz, 2H),7.93 (m, 2H), 8.15 (m, 2H). 31P NMR (121 MHz, CDCl3) δ 17.63.

Quelle