反应详情

To a solution of 33.9 g (0.112 mole) of 2-bromo-6 -methoxy-3-phenylbenzofuran in 1 l. of acetic acid is added 21.2 g (0.168 mole) of cyclohexene-4-carboxylic acid, then 15.5 g (0.168 mole) of dinitrogen tetraoxide in 20 ml of acetic acid is added dropwise over 1.5 hours. After 3 additional hours the mixture is poured into cold water to give a yellow gum. The mixture is treated with diethyl ether and the solid residue is collected by filtration. This residue is recrystallized from aqueous ethanol, cyclohexane and ethanol to provide yellow solid 6-methoxy-2-nitro-3-phenylbenzofuran, m.p. 100°-106° C., containing 20 % 7-bromo-6-methoxy-2-nitro-3-phenylbenzofuran.

1. customto give a yellow gum
2. filtrationthe solid residue is collected by filtration
3. customThis residue is recrystallized from aqueous ethanol, cyclohexane and ethanol