Hydrothermal synthesis of molecular oxovanadium compounds.: The crystal and molecular structures of [VO2(terpy)]NO3, [VO(terpy)(OH3PC6H5)2] [{Cu(H2O)(terpy)}V2O6], [{Cu(ttbterpy)}V2O6] and [{Cu(ttbterpy)}VO2( HO3PCH2PO3)] • H2O (terpy=2,2′:6′,2"-terpyridine; ttbterpy=4,4,4"-tri-tert-butyl-2,2: 6′, 2"-terpyridine)

Hydrothermal conditions have been exploited in the syntheses of five molecular oxovanadium species [VO2(terpy)]NO3 center dot H2O (1 center dot H2O), [VO(terpy)(HO3PC6H5)(2)] (2), [{Cu(H2O)(terpy)}V2O6]center dot H2O (3 center dot H2O), [{Cu(ttbterpy)} V2P6]center dot 2H(2)O (4 center dot 2H(2)O), and [{Cu(ttbterpy)}VO2(HO3PCH2PO3)]center dot H2O (5 center dot H2O). The binuclear molecular cation of compound 1 exhibits a planar {V2O4)(2+) core from the fusion of two cis-oxovanadium(V) units. Compound 2 is a six coordinate V(IV) species with {VO3N3} coordination geometry. Compounds 3 and 4 are constructed from the common {V4O12}(4-) cluster with peripheral Cu(II)-ligand subunits. The Cu(II) square pyramids of the [{Cu(H2O)(terpy)}(2)V4O12] cluster of 3 share a single vertex with the vanadate cluster as a consequence of coordination of an aqua ligand. In contrast, in ({Cu(ttbterpy)}(2)V4O12] (4), each Cu(II) square pyramid shares two vertices with the vanadate core. Of the materials of this study, only compound 5 incorporates both Cu(II) and diphosphonate into the final product. The structure of the dimer consists of a cyclic {V2P2O4} core linked through diphosphonate ligands to two peripheral {Cu(ttbterpy)}(2+) units. (c) 2006 Elsevier B.V. All rights reserved.