A method for producing a 1,2,4-oxadiazol derivative represented by the formula (1): (1) [wherein, R
1
represents a methyl group or a phenyl group, and R
2
represents an optionally substituted linear or branched alkyl group], which comprises reacting a nitrile represented by the formula (2): (2) [wherein, R
2
represents an optionally substituted linear or branched alkyl group] with acetone or acetophenone in the presence of iron (III) nitrate. The method allows a 1,2,4-oxadiazol derivative exhibiting a useful biological activity to be produced in good yield without the discharge of a harmful waste.
The reaction of nitriles and acetophenone with iron(III) nitrate at 80 °C gave the corresponding 3-benzoyl-1,2,4-oxadiazole derivatives. Moreover, in this reaction using acetone, the 3-acetyl-1,2,4-oxadiazole derivatives were obtained.