Reaktion #7877

Reaktionsgleichung

2-[3-methoxy-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl]-1,3-benzoxazole

2-bromopyridine

→

2-[4-(6-bromopyridin-2-yl)-3-methoxyphenyl]-1,3-benzoxazole

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeThe flask was evacuated
2. 2
   workup.ADDITIONfilled with argon and DME (5 mL)
3. 3
   workup.ADDITIONwas added
4. 4
   SonstigeThe suspension was deoxygenated with a stream of argon for 10 min
5. 5
   Sonstigepurified by automated flash chromatography

Vorschrift

2-[3-methoxy-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl]-1,3-benzoxazole (200 mg, 0.57 mmol) CsF (350 mg, 2.3 mmol), Pd(Ph3P)4 (65 mg, 0.057 mmol), and 2-bromopyridine (140 mg, 0.57 mmol) were combined in a 2-neck flask. The flask was evacuated and filled with argon and DME (5 mL) was added. The suspension was deoxygenated with a stream of argon for 10 min. The reaction mixture was stirred under argon at 80° C. for 24 h. Crude mixture was adsorbed onto silica gel and purified by automated flash chromatography using and EtOAc/hexanes gradient to afford the desired 2-[4-(6-bromopyridin-2-yl)-3-methoxyphenyl]-1,3-benzoxazole as a colorless solid: 1H NMR (CDCl3, 300 MHz) δ 8.08–8.05 (d, 1H), 7.98–7.95 (m, 2H), 7.89 (s, 1H), 7.84–7.79 (m, 1H), 7.63–7.60 (m, 1H), 7.45–7.38 (m, 3H), 4.02 (s, 3H). MS (ESI) 382 (M+H)+.

Quelle