Cationic cobaltammines as anion receptors: Synthesis, characterization and X-ray structure of bis-(hexaamminecobalt(III)) tris-(hydrogenarsenate) tetrahydrate

✍ Scribed by Ritu Bala; Raj Pal Sharma; Rajni Sharma; Juan M. Salas; Miguel Quirós; William T.A. Harrison

• Publisher: Elsevier Science
• Year: 2007
• Tongue: English
• Weight: 390 KB
• Volume: 828
• Category: Article
• ISSN: 0022-2860
• DOI: 10.1016/j.molstruc.2006.05.047

✦ Synopsis

The orange coloured single crystals of bis-(hexaamminecobalt(III)) tris-(hydrogenarsenate) tetrahydrate, [Co(NH 3 ) 6 ] 2 (HA-sO 4 ) 3 AE4H 2 O, have been prepared by reacting aqueous solutions of hexaamminecobalt(III) chloride with disodium hydrogenarsenate in 1:1 molar ratio. The title complex salt was characterized by elemental analyses and spectroscopic studies (IR, UV/visible). X-ray crystal structure determination of the title complex salt revealed the presence of discrete ions, i.e., cation [Co(NH 3 ) 6 ] 3+ and anion HAsO 4 2À and four water molecules in the solid state. A strong network of hydrogen bond interactions (N-HÁ Á ÁO (hydrogenarsenate), N-HÁ Á ÁO (water), O-HÁ Á ÁO (hydrogenarsenate)) stabilize the crystal lattice. The formation of definite salt and measurement of solubility products suggest that [Co(NH 3 ) 6 ] 3+ may be used as an anion receptor for hydrogenarsenate anion.