Syntheses and crystal structures of the first organically templated metal tellurites

The first organically templated vanadium tellurites, [H2en][(VO2)(TeO3)]2·H2O (1, en=ethylenediamine) and [H2pip][(VO2)(TeO3)]2 (2, pip=piperazine) have been synthesized by hydrothermal reactions and structurally characterized. Both compounds feature a [(VO2)(TeO3)]− anionic layer containing V2Te2 four-member rings and V4Te4 eight member rings. The vanadium (V) atom is five coordinated by three tellurite oxygens and two terminal oxygen atoms in a distorted trigonal bipyramidal geometry. The interconnection of the VO5 polyhedra by bridging tellurite groups leads to a 2D corrugated anionic inorganic layer. The doubly protonated template cations and the lattice water molecules in 1 are located at the interlayer space and are involved in hydrogen bonding. The doubly protonated template cation in 2 is not involved in hydrogen bonding with the anionic inorganic layer.