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.