反应详情

A mixture of 372 mg (2.346 mmol) of 3-chloro-5-methoxyphenol (B-1), 947 mg (4.692 mmol) of 5-bromopyridine-3-boronic acid (13-1), 426 mg (2.346 mmol) of copper (II) acetate and 4.0 g of freshly activated powdered 4A molecular sieves was stirred in 20 mL of DCM in a screw top glass sealed tube. The reaction was then treated with 1.635 mL (11.73 mmol) of triethylamine and the vessel was loosely capped. The mixture was vigorously stirred at room temperature for 48 hours. The mixture was filtered through a pad of celite and the filtrate was concentrated in vacuo to a black residue. The residue was purified on a CombiFlash silica column eluted with an ethyl acetate:hexanes gradient to give the desired product 13-2 as an oil (Rf=0.7, EtOAc:hexanes 1:4). MS: M+1=314. 1H NMR(CDCl3): 3.79 (s, 3H), 6.47 (m, 1H), 6.61 (m, 1H), 6.74 (m, 1H), 7.46 (m, 1H), 8.33 (d, 1H), 8.46 (d, 1H).

1. customsealed tube
2. customthe vessel was loosely capped
3. filtrationThe mixture was filtered through a pad of celite
4. concentrationthe filtrate was concentrated in vacuo to a black residue
5. customThe residue was purified on a CombiFlash silica column
6. washeluted with an ethyl acetate