Synthesis of sterically hindered tris(4-imidazolyl)carbinol ligands and their copper(I) complexes related to metalloenzymes

Tris(4-imidazolyl)carbinol, which has close coordination environment to the active site of metalloenzymes, has not been utilized as a biomimetic ligand because of its instability. We have synthesized stable tris(4-imidazolyl)carbinol derivatives having a methyl group as the NH protective group and a bulky substituent on the imidazole ring for stabilizing reactive species bound to the metal center. These ligands provide stable monomeric copper(I) complexes whose coordination environment are very close to the active site of metalloenzymes.