反応 #1880946

反応方程式

4-(2-hydroxyethyloxy)-3-bromo-4′-cyanoazobenzene

copper cyanide

ammonia

→

4-(2-Hydroxyethyloxy)-3,4′-dicyanoazobenzene

溶媒

DMF

反応条件

後処理

1. 1
   ろ過the precipitate is filtered off
2. 2
   workup.DISSOLUTIONThe precipitate is dissolved in hot dioxane
3. 3
   ろ過The solution is filtered off from the undissolved residue
4. 4
   その他the dioxane is evaporated off on a rotary evaporator
5. 5
   その他the product is purified by chromatography on silica gel in toluene/THF (½)
6. 6
   その他recrystallized once from ethanol

実験手順

15 g (4-(2-hydroxyethyloxy)-3-bromo-4′-cyanoazobenzene are dissolved in 25 ml hot DMF. 4.3 g copper cyanide are then added and the reaction mixture is stirred at 140° C. for 5–6 hours. This solution is added to approx. 500 ml of a 13% aqueous ammonia solution and the precipitate is filtered off. The precipitate is dissolved in hot dioxane. The solution is filtered off from the undissolved residue, the dioxane is evaporated off on a rotary evaporator and the product is purified by chromatography on silica gel in toluene/THF (½) and recrystallized once from ethanol. The yield of 4-(2-hydroxyethyloxy)-3,4′-dicyanoazobenzene is 4.5 g. M.p.=138° C.; max=356 nm (DMF).

出典