Second-sphere coordination complex via hydrogen bonding: synthesis, characterization and X-ray crystal structure of hexaamminecobalt(III)chloride dimethanesulphonate, [Co(NH3)6]Cl(CH3SO3)2

Cationic cobaltammines as anion receptors: a convenient synthesis and the X-ray structure of hexaamminecobalt(III) chloride dichromate monohydrate

“…The [Co(NH 3 ) 6 ] 3þ , Cl -, Cr 2 O 7 2-ions and water molecule are held together by electrostatic forces and hydrogen bonding of the type O-HÁ Á ÁO, N-HÁ Á ÁCl -and O-HÁ Á ÁCl -, resulting in a three-dimensional hydrogen-bonded network through the second sphere coordination (figure 1), similar to that present in [Co(NH 3 ) 6 ]Cl(CH 3 SO 3 ) 2 [30] . The X-ray structure determination of [Co(NH 3 ) 6 ]Cl(CH 3 SO 3 ) 2 revealed an interesting network of N-HÁ Á ÁO and N-HÁ Á ÁCl -hydrogen bonds that serve to stabilize layers in the lattice.…”

“…A special feature is the presence of a ''sandwiched'' water molecule between the hexaamminecobalt(III) cation and the dichromate anion. In [Co(NH 3 ) 6 ] 3þ , the cobalt(III) ion possesses nearly regular [29] and hexaamminecobalt(III) chloride dimethanesulfonate [30]. The dichromate anion (Cr 2 O 2À 7 ) has two bonding modes with metal or ammonium ions, ionic [39][40][41][42][43] and bidentate [44,45] (bridging).…”

“…This paper reports the use of hexaamminecobalt(III) as an anion receptor for the dichromate ion. The synthesis, characterization and single-crystal X-ray structure determination of hexaamminecobalt(III) chloride dichromate monohydrate, [Co(NH 3 ) 6 ]ClCr 2 O 7 Á H 2 O, is the continuation [22][23][24][25][26][27][28][29][30][31] of our interest in the structural chemistry of cobalt(III) complexes. We have previously reported the use of hexaamminecobalt(III) as an anion receptor for other oxoanions [29][30][31].…”

Binding of fluorine containing anions by new cationic Co(III) complex: Competitive interaction of chloride and hexafluorophosphate with [Co(phen)(H2biim)2]3+

“…6 ]Cl 3 in which partial replacement of chloride ions was achieved even though the reaction stoichiometry was conducive for total replacement (methanesulphonate, mesitylenesulphonate, BF 4 À and p-nitrobenzoate) [36][37][38][39].…”

Second-sphere coordination in anion binding: sodium hexaamminecobalt(III) tetrakis(4-fluorobenzoate) monohydrate

“…We are currently engaged in studies to explore cobalt(III) complexes as potential anion receptors and have reported previously the crystal structures of some hexaamminecobalt(III) salts with organic sulfonate (Sharma et al, 2004) and benzoate anions (Sharma et al, 2005). The cation [Co(NH 3 ) 6 ] 3+ has also been characterized previously in several structures containing organic carboxylate anions, including [Co(NH 3 ) 6 ] 2 (Ox) 3 Á4H 2 O (Ox is oxalate; Gorol et al, 2000) and [Co(NH 3 ) 6 ][(NpO 2 ) 2 (HMal)(Mal)](Mal) (Mal is malonate; Grigor'ev et al 2004).…”