Reaktion #338137

Reaktionsgleichung

3-Tributylstannanyl-pyridine-2-carbaldehyde

methyl 3-bromobenzoate

→

3-(2-Formyl-pyridin-3-yl)-benzoic acid methyl ester

Ausbeute 17.6%

Lösungsmittel

DMF

NaHCO3

EtOAc

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturThe reaction was cooled to room temperature
2. 2
   SonstigeThe organic phase was separated
3. 3
   Waschenwashed with brine (3×15 mL)
4. 4
   Trocknendried (MgSO4)
5. 5
   Filtrationfiltered
6. 6
   Einengenconcentrated under reduced pressure
7. 7
   SonstigePurification by flash chromatography on silica gel (Hexanes/EtOAc, 60:40)

Vorschrift

A stirred solution of 3-Tributylstannanyl-pyridine-2-carbaldehyde (256 mg, 0.65 mmol) and methyl 3-bromobenzoate (128 mg, 0.59 mmol) in DMF (2.1 mL) was degassed with Ar for 5 minutes, after which PdCl2(PPh3)2 (25 mg, 0.036 mmol) and CuO (34 mg, 0.43 mmol) was added and the mixture heated to 110° C. overnight. The reaction was cooled to room temperature, and diluted with saturated aqueous NaHCO3 (15 mL) and EtOAc (40 mL). The organic phase was separated, washed with brine (3×15 mL), dried (MgSO4), filtered, and concentrated under reduced pressure. Purification by flash chromatography on silica gel (Hexanes/EtOAc, 60:40) gave 3-(2-Formyl-pyridin-3-yl)-benzoic acid methyl ester (25 mg, 17%) as a white solid. 1H NMR (CDCl3) δ 3.92 (s, 3H), 7.47-7.56 (m, 2H), 7.58 (d, 1H, J=4.9 Hz), 8.03 (s, 1H), 8.07-8.20 (m, 1H), 8.86 (dd, 1H, J=4.9, 1.8 Hz), 10.08 (s, 1H).

Quelle