反应详情

Cyanogen bromide (0.7 g, 0.0067 mole) is added to a solution of 3,5-bis(1,1-dimethylethyl)-4-hydroxycinnamic acid, hydrazide (1.9 g, 0.0067 mole) and sodium bicarbonate (0.56 g, 0.0067 mole) in dioxane (10 ml)/water (10 ml). The resulting mixture is stirred two hours at room temperature. The solution is concentrated to half volume in vacuo and the residue diluted with water. The resulting solid is filtered and recrystallized from ethyl acetate/hexane to provide 1.1 g (2.1 g theor., 52%) of (E)-4-[2-(5-amino-1,3,4-oxadiazole-2-yl)ethenyl]-2,6-bis(1,1-dimethylethyl)phenol after drying in vacuo at room temperature, mp 221° C.

1. concentrationThe solution is concentrated to half volume in vacuo
2. additionthe residue diluted with water
3. filtrationThe resulting solid is filtered
4. customrecrystallized from ethyl acetate/hexane