Reactions of a Coordination Polymer Based on the Triangular Cluster [Cu3(μ3-OH)(μ-pz)3]2+ with Strong Acids. Crystal Structure and Supramolecular Assemblies of New Mono-, Tri-, and Hexanuclear Complexes and Coordination Polymers

A series of mono-, tri-, hexanuclear compounds, and coordination polymers were obtained from the reaction of [Cu-3(mu(3)-OH)(mu-pz)(3)(MeCOO)(2)(Hpz)], 1, (Hpz = pyrazole) with H2SO4, H3PO4, HClO4, HNO3, CF(3)COOh, and CF3SO3H. The trinuclear [Cu-3(mu(3)-OH)(p-pz)(3)(SO4)(Hpz)(3)] center dot (HO)-O-2, 2(t), forms a one-dimensional coordination polymer through bridging SO42-. The mononuclear [Cu(mu H-2(4))(2)(Hpz)(4)], 3(m), is instead the unique (pure) compound isolated in our conditions from the reaction of I with H3PO4, whereas both [Cu(ClO4)(2)(HPz)(4)], 4(m), and [{Cu-3(mu(3)-OH)(mu-pz)(3)(ClO4)(Hpz)(3)}(2)(mu(2)-ClO4), 4(h), have been isolated from the reaction with aqueous HClO4, the latter being a hexanuclear species formed by two trinuclear triangular units connected through two bridging perchlorates. Moreover, the three already reported species [Cu-3(mu 3-OH)(p-pz)(3)(NO3)(mu-3-NO3)(Hpz)(2)], 5(t), [{Cu-3(mu(3)-OH)(mu-pz)(3)(NO3)(Hpz)(3)(mu(2)-NO3)(2)], 5(h), and [Cu(NO3)(2)(Hpz)(4)], 5(h), are formed in the reaction of 1 with HNO3. Three pure fractions, containing crystals of the trinuclear [Cu-3(mu(3)-Oh)(p-pz),(CF3COO)(2)(Hpz)(2)] 6(t), and two mononuclear adducts, [Cu(CF3COO)(2)(HPz)(4)], 6(m(a)), and [Cu(CF3COO)(2)(Hpz)2j, 6 have been isolated when 1 was reacted with aqueous CF3COOH. Analogously, in the reaction of 1 with CF3SO3H, three different species were obtained, the mononuclear [Cu(CF3SO3H)(2)(Hpz)(4)], 7(m), the trinuclear [Cu-3(mu(3)-OH)(mu-pz)(3)(CF3SO3)(2)(Hpz)(3)]center dot H2O, 7(t), and the hexanuclear [{Cu-3(mu(3)-OH)(mu-pz)(3)(Hpz)(3)}{Cu-3(mu(3)-O)(mu-pz)(3)(Hpz)(3)}](CF3SO3)(3), 7h, where the two trinuclear units are strongly bonded through an unequally shared Fl-bond involving (mu(3)-OH) and (mu(3)-O) [O center dot center dot center dot O 2.54(1) angstrom, O(2)-H(2)H(2)center dot center dot center dot O(1) 180 degrees]. All compounds were fully characterized by single-crystal X-ray diffraction determinations, UV-vis and IR spectra, electrospray ionization mass spectrometry, and magnetic susceptibility measurements.