The first complex of azidopentaamminecobalt(III) containing organic anion: Synthesis, characterization and X-ray structure determination of azidopentaamminecobalt(III) p-nitrobenzoate dihydrate

Violet coloured single crystals of azidopentaamminecobalt(III) p-nitrobenzoate dihydrate, [Co(NH3)5N3](NO2C6H4COO)2·2H2O has been prepared by reacting hot aqueous solutions of azidopentaamminecobalt(III) chloride and sodium salt of p-nitrobenzoic acid in 1:2 M ratio. The newly synthesized complex salt was characterized by elemental analyses and spectroscopic studies (IR, UV/Visible & 1H NMR). A single crystal X-ray structure determination revealed the presence of one cation, two anion and two water molecules. Crystal lattice is stabilized by electrostatic forces of attraction and hydrogen bonding interactions. This is the first X-ray structure determination of azidopentaamminecobalt(III) complex with p-nitrobenzoate anion.