反応 #2328988

反応方程式

sodium bicarbonate

N-(2-Hydroxy-4-methoxyphenyl)-6-(methylamino)nicotinamide

acetic acid

→

N-[5-(6-methoxy-1,3-benzoxazol-2-yl)pyridin-2-yl]-N-methylacetamide

title compound

5-(6-Methoxy-1,3-benzoxazol-2-yl)-N-methylpyridin-2-amine

溶媒

water

反応条件

後処理

1. 1
   抽出The aqueous solution was extracted three times with diethyl ether
2. 2
   洗浄the combined organic layers were washed with brine
3. 3
   乾燥dried (MgSO4)
4. 4
   その他evaporated
5. 5
   その他The crude product was purified first by flash column chromatography (hexane/ethyl acetate-gradient; 30-50% ethyl acetate)

実験手順

N-(2-Hydroxy-4-methoxyphenyl)-6-(methylamino)nicotinamide (0.23 g, 0.84 mmol) was mixed with acetic acid (4 mL) and the reaction was run in a microwave reactor at 200° C. for 25 minutes. The reaction mixture was added to water and made basic with sodium bicarbonate (sat. aq.). The aqueous solution was extracted three times with diethyl ether and the combined organic layers were washed with brine, dried (MgSO4) and evaporated. The crude product was purified first by flash column chromatography (hexane/ethyl acetate-gradient; 30-50% ethyl acetate), followed by preparative HPLC, resulting in the isolation of N-[5-(6-methoxy-1,3-benzoxazol-2-yl)pyridin-2-yl]-N-methylacetamide (6 mg) as a minor product, together with the title compound (0.13 g) as a solid. 1H NMR (400 MHz, CHLOROFORM-d) δ ppm 8.90 (d, 1H) 8.23 (dd, 1H) 7.59 (d, 1H) 7.10 (d, 1H) 6.94 (dd, 1H) 6.52 (d, 1H) 5.26 (br. s, 1H) 3.89 (s, 3H) 2.82-3.16 (m, 3 H); MS m/z (M+H) 256.

出典