Couplers for hair coloring compositions for oxidative dyeing of hair are compounds of the formula at least one coupler comprising a compound of the formula (1): wherein R is selected from of C1 to C2 alkyl and hydroxyethyl, R1 and R2 are each independently selected from the group consisting of C1 to C5 alkyl, C3 to C6 cycloalkyl, C1 to C5 alkoxy, C1 to C5 hydroxyalkyl, C1 to C5 hydroxyalkoxy, or R1 and R2 together with the carbon atom to which they are attached form a C3 to C6 cycloalkyl group.