Syntheses and Crystal Structures of Seven-Coordinate (Ethylenediamine-N,N,N′,N′-tetraacetato)aquavanadate(III) Complexes

K[V(edta)(H2O)]·2H2O (1a) was prepared by the reaction of VCl3 with K4 edta. The compound was converted to its sodium and ammonium salts by use of a cation exchange resin. Crystal structure analyses of Na[V(edta)(H2O)]·3H2O (1b) and NH4[V(edta)(H2O)]·2.5H2O (1c) revealed that in both compounds the vanadium atom adopts a capped trigonal-prismatic structures with a hexadentate ethylenediammetetraacetato ligand and an aqua ligand. Crystal data are as follows: 1b: Monoclinic, P21⁄a, a=17.831 (3), b=8.408 (1), c=11.595 (2) Å, β=109.39 (1)°, Z=4, R=0.045 for 6321 reflections; 1c: Monoclinic, Aa, a=8.552 (1), b=59.948 (6), c=7.226 (Å), β=114.95 (1)°, Z=8, R=0.050 for 6087 reflections.