Di- tert -alkyl-substituted catechols with a heterocyclic imidazole-type substituent were synthesized in three steps from catecholaldehydes. The 1,1,4,4-tetramethylbutanediyl substituent was shown to be resistant to the action of acids in the demethylation reaction. The isomerization of 3,4,5-substituted catechols to the 3,4,6-substituted isomers was observed. The molecular structures of the synthesized compounds in the crystalline state were established by X-ray diffraction analysis. For the catechol derivatives, the tertiary substituent in the ortho position to the imidazole moiety was shown to have an effect on the mutual arrangement of the catechol and heterocyclic moieties. The electrochemical properties of the synthesized imidazole-containing catechols were studied and their anti-radical activity was evaluated by the 2,2-diphenyl-1-picrylhydrazyl assay.