Cation dependent formation of hybrid organic-inorganic frameworks based on the strandberg-type polyanion [(O2CCH2PO3)2Mo5O15]6- and Cu2+ ions

We present the first examples of materials based on the Strandberg type polyanion [(O2CCH2PO3)(2)Mo5O15](6-), linked by Cu2+ centers via coordination to the carboxylate functions of the polyanion. Simple one-pot reaction of Rb4KNa[(O2CCH2PO3)(2)Mo5O15]center dot H2O with CuCl2 center dot 2H(2)O in aqueous acidic media followed by crystallization resulted in the three hybrid organic-inorganic materials {K2.6Rb1.4[(PO3CH2CO2)(2)Mo5O15Cu(H2O)(3)]center dot 7H(2)O} (n) (KRb-1), {Na2Cs3[(PO3CH2CO2)(2)Mo5O15(Cu(H2O)(2)Cl)]center dot 6H(2)O} (n) (NaCs-2) and {Na2.75Rb1.25[(PO3CH2CO2)(2)Mo5O15Cu(H2O)(3)]center dot 9H(2)O} (n) (NaRb-3), which were characterized by single-crystal X-ray diffraction, IR, TGA and elemental analysis. All three compounds are 1:1 polymers of the polyanion and the Cu2+ centers are all five-coordinate with two carboxylate oxygens in a trans fashion. However, the chains in KRb-1, NaCs-2 and NaRb-3 are packed differently along b leading to different solid state structures, indicating an important role of the alkali counter cations.