By reacting water solutions of pyrazole (Hpz) with copper(II) fumarate or 2-methylfumarate in solvothermal conditions two almost identical trinuclear triangular complexes, [Cu-3(mu(3)-OH)(mu-pz)(3){R(COO)(2)}(Hpz)], [R = CH = CH, C(CH3) = CH], have been obtained. The two carboxylate groups of both fumarate and 2-methylfumarate show different arrangements, one acting as monotopic ligand while the other one has a ditopic behavior. Thus, in both cases, wavy 2D isomorphous Coordination Polymers (CPs), that further self-assemble through strong H-bonds into two 3D networks, have been obtained. When copper(II) 2-methylfumarate was reacted with pyrazole at r.t. the mononuclear [Cu(Hpz)(2)(H2O)(2-methylfumarate) center dot H2O] complex was, in addition, obtained. In this case the bridging dianions produce instead monodimensional CPs that self-assemble into supramolecular tapes mediated by H-bond interactions, involving coordinated and crystallization water molecules. The mononuclear and trinuclear species were preliminary tested as catalysts for the oxidation of styrene by H2O2.
Coordination polymers based on trinuclear and mononuclear copper-pyrazolate building moieties connected by fumarate or 2-methylfumarate ions
DI NICOLA, CORRADO;PETTINARI, Claudio
2012-01-01
Abstract
By reacting water solutions of pyrazole (Hpz) with copper(II) fumarate or 2-methylfumarate in solvothermal conditions two almost identical trinuclear triangular complexes, [Cu-3(mu(3)-OH)(mu-pz)(3){R(COO)(2)}(Hpz)], [R = CH = CH, C(CH3) = CH], have been obtained. The two carboxylate groups of both fumarate and 2-methylfumarate show different arrangements, one acting as monotopic ligand while the other one has a ditopic behavior. Thus, in both cases, wavy 2D isomorphous Coordination Polymers (CPs), that further self-assemble through strong H-bonds into two 3D networks, have been obtained. When copper(II) 2-methylfumarate was reacted with pyrazole at r.t. the mononuclear [Cu(Hpz)(2)(H2O)(2-methylfumarate) center dot H2O] complex was, in addition, obtained. In this case the bridging dianions produce instead monodimensional CPs that self-assemble into supramolecular tapes mediated by H-bond interactions, involving coordinated and crystallization water molecules. The mononuclear and trinuclear species were preliminary tested as catalysts for the oxidation of styrene by H2O2.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
