反応 #62747

反応方程式

water

ethylcyanoacetate

7,8-dimethoxy-5-formyl-2H-1-benzopyran

piperidine

→

orange solid

収率 66.9%

Ethyl 2-cyano-3-(7,8-dimethoxy-2H-1-benzopyran-5-yl)propenoate

収率 66.9%

溶媒

benzene

反応条件

後処理

1. 1
   温度was heated
2. 2
   温度to cool
3. 3
   抽出The solution was extracted successively with water (200 mL), 0.5N hydrochloric acid (200 mL), saturated sodium bicarbonate solution (200 mL), H2O (200 mL)
4. 4
   乾燥dried over magnesium sulfate
5. 5
   その他The volatiles were removed under reduced pressure

実験手順

A mixture of ethylcyanoacetate (11.3 g, 0.1 mole), 7,8-dimethoxy-5-formyl-2H-1-benzopyran (22.0 g, 0.1 mole), piperidine (1.02 g, 0.01 mole) and acetic acid (0.36 g, 0.006 mole) in benzene (100 mL) was heated at reflux for 5 hr with azeotropic removal of water and allowed to cool. The solution was extracted successively with water (200 mL), 0.5N hydrochloric acid (200 mL), saturated sodium bicarbonate solution (200 mL), H2O (200 mL) and dried over magnesium sulfate. The volatiles were removed under reduced pressure to give 21.1 g (66.9%) of an orange solid, mp 104.5°-107.5° C.

出典