Macrocyclic Copper(II) and Zinc(II) Complexes Incorporating Phosphate Esters

Slow evaporation of solutions prepared by adding either Cu(ClO4)2·6H2O or Zn(ClO4)2·6H2O to solutions containing appropriate proportions of Me3tacn (1,4,7-trimethyl-1,4,7-triazacyclononane) and sodium phenyl phosphate (Na2PhOPO3) gave dark blue crystals of [Cu3(Me3tacn)3(PhOPO3)2](ClO4)2·1/2H2O (1) and colorless crystals of [Zn2(Me3tacn)2(H2O)4(PhOPO3)](ClO4)2·H2O (2), respectively. Blue crystals of [Cu(tacn)2](BNPP)2 (3) formed in an aqueous solution of [Cu(tacn)Cl2], bis(p-nitrophenyl phosphate) (BNPP), and HEPES buffer (pH 7.4). Compound 1 crystallizes in the triclinic space group P1̄ (No. 2) with a = 9.8053(2) Å, b = 12.9068(2) Å, c = 22.1132(2) Å, α = 98.636(1)°, β = 99.546(1)°, γ = 101.1733(8)°, and Z = 2 and exhibits trinuclear Cu(II) clusters in which square pyramidal metal centers are capped by two phosphate esters located above and below the plane of the metal centers. The trinuclear cluster is asymmetric having Cu···Cu distances of 4.14, 4.55, and 5.04 Å. Compound 2 crystallizes in the monoclinic space group P21/c (No. 14) with a = 13.6248(2) Å, b = 11.6002(2) Å, c = 25.9681(4) Å, β = 102.0072(9)°, and Z = 4 and contains a dinuclear Zn(II) complex formed by linking two units of [Zn(Me3tacn)(OH2)2]2+ by a single phosphate ester. Compound 3 crystallizes in the monoclinic space group C2/c (No. 15) with a = 24.7105(5) Å, b = 12.8627(3) Å, c = 14.0079(3) Å, β = 106.600(1)°, and Z = 4 and consists of mononuclear [Cu(tacn)2]2+ cations whose charge is balanced by the BNPP- anions.