反応 #498410

反応方程式

2,6-dimethyl-3-aminopyridine

diethyl ethoxymethylenemalonate

→

title compound

収率 30.0%

Ethyl 4-Hydroxy-6,8-dimethyl-1,7-naphthyridine-3-carboxylate

収率 30.0%

溶媒

xylene

反応条件

後処理

1. 1
   その他allowing for removal of ethanol
2. 2
   その他After the solvent is removed
3. 3
   温度The mixture is then heated
4. 4
   温度to reflux with removal of ethanol for 30 min
5. 5
   workup.ADDITIONhexanes (20 mL) is added
6. 6
   ろ過The resulting precipitate is filtered
7. 7
   洗浄washed with diethyl ether (2×10 mL)
8. 8
   その他dried

実験手順

A mixture of 2,6-dimethyl-3-aminopyridine (0.85 g) and diethyl ethoxymethylenemalonate (1.53 g) is heated at 135° C. in xylene (30 mL) for 2 h allowing for removal of ethanol. After the solvent is removed, the mixture is suspended in diphenyl ether (15 mL). The mixture is then heated to reflux with removal of ethanol for 30 min. The reaction mixture is cooled to room temperature and hexanes (20 mL) is added. The resulting precipitate is filtered, washed with diethyl ether (2×10 mL) and dried to give 0.5 g (30%) of the title compound as a brown solid. Physical chracteristics: MS (ESI+) m/z 247 (M+H)+; 1H NMR (DMSO) δ 8.67, 7.97,4.38, 2.85,2.67, 1.40.

出典