Copper(I) complexes of tripodal tris(N-methyl-4,5-diphenyl-imidazolyl) methane ligands, N3CR (1a-c, R = OH, OMe, H), have been prepared as models for the Cu(A) site of copper hydroxylase enzymes. In the absence of additional donors, the ligands 1 react with [Cu(CH3CN)(4)]PF6 (2) to produce dinuclear complexes [(N3CR)(2)Cu-2](PF6)(2) (3) in which the tripodal ligands bridge two trigonal Cu centers; the structures of 3b and 3c are established by X-ray diffraction. Mononuclear adducts [(N3CR)CuL]Z are produced with L = acetonitrile (4), carbon monoxide (5), and t-BuNC (6, 7). The carbonyl complexes 5 are in dynamic equilibrium with the dimeric complexes 3, but 5c (R = H) can be isolated. The structures of the isocyanide derivatives depend critically on the tripod methane substituent, R. Thus, the X-ray structures of 6 (R = OMe) and 7 (R = H) show trigonal and tetrahedral geometries, respectively, with bi- or tridentate coordination of the tripod. A trinuclear complex [Cu-3(N3COH)(2)(t-BuNC)(2)](PF6)(3) (8) is formed from N3COH (1a) which features both three-coordinate and two-coordinate Cu atoms and bidentate tripod coordination. Reactions of dioxygen with dinuclear 3c or mononuclear [(N3CR)CuL]Z are sluggish, producing from the latter in acetone [(N3CH)Cu-II(L)(L')](PF6)(2) (9, L = acetone, L' = H2O).