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

Abstract

2005) Cationic cobaltammines as anion receptors: a convenient synthesis and the X-ray structure of hexaamminecobalt(III) chloride dichromate monohydrate, Journal of Coordination Chemistry, 58:3, 217-223, Orange-colored single crystals of hexaamminecobalt(III) chloride dichromate monohydrate, [Co(NH 3 ) 6 ]ClCr 2 O 7 Á H 2 O, were prepared by reacting hot aqueous solutions of hexaamminecobalt(III) chloride and potassium dichromate in a 1:1 molar ratio and allowing the mixture to cool slowly to room temperature. The salt was characterized by elemental analyses and spectroscopic studies. A single-crystal X-ray structure determination revealed that the salt crystallizes in space group P2 1 /c with a ¼ 10.0218(9), b ¼ 9.3216(8), c ¼ 16.2203(13) Å , ¼ 112.962(6) , V ¼ 1395.2(2) Å 3 , Z ¼ 4 and R ¼ 0.0326. In the salt, a strong network of hydrogen bonds (predominantly N-HÁ Á ÁO, N-HÁ Á ÁCl -) between the hexaamminecobalt(III) cation, the water molecule, the chloride ion and oxygen atoms of the dichromate ion represents the second sphere coordination and suggests that [Co(NH 3 ) 6 ] 3þ may be used as an anion receptor for the dichromate ion.

Approaching Dissolved Species in Ammonoacidic GaN Crystal Growth: A Combined Solution NMR and Computational Study

“…The distances match those reported for NH···Clh ydrogen bonds in organic crystals( 320-334 pm for NH···Cl and NH + ···Cl units based on the sum of hydrogen bond radii [20] and the same structuralm otif with N···Cl distances ranging from 326.7(2)-352.4(3) pm was also found in crystal structures of some hexammine cobalt complexes. [21] Attachment of chlorides induces structurald istortions, which are evidenced by al arger varianceo fi ndividual Ga-N distances in some assemblies and ag eneral contraction of the coordination polyhedra with increasing number of anions (cf. Figure S4 Subsequentmagnetic shieldingc alculations were carried out using the zero order regular approximation( ZORA) [22] in order to account in ac onsistentm anner for spin-orbit induced effects associatedw itht he presence of heavy atom substituents [23] (X = Br,I ).…”

First X-ray structure of hexaamminecobalt(III) salt with complex fluoroanion: Synthesis and characterization of [Co(NH3)6]X·SiF6·nH2O, where X=Cl, Br, I and NO3 and crystal structure of [Co(NH3)6]Cl·SiF6·2H2O

“…However, in the case of hexaamminecobalt(III) chloride dimethanesulfonate [13] there are appreciable shifts of absorption bands (l max 430; 373 nm). (12) at À127.8 ppm due to SiF 6 2À ion (Fig. 2).…”

“…1 T 1g transition.) [12]. However, in the case of hexaamminecobalt(III) chloride dimethanesulfonate [13] there are appreciable shifts of absorption bands (l max 430; 373 nm).…”

“…Although the synthesis and single crystal X-ray structure determinations of a variety of hexaamminecobalt(III) complex salts have been reported in the literature [2,3,[7][8][9], particularly with metal chloroanions [MCl 5 ] 2À and [MCl 6 ] 3À [1] but none with complex fluoroanion. In continuation of our interest [10][11][12][13] in hexaaminecobalt(III) complex salts the present work reports synthesis and spectroscopic studies of [Co(N H 3 ) 6 ]XSiF 6 ÁnH 2 O where X = Cl (n = 2), Br, I, NO 3 (n = 0) and single crystal X-ray structure determination of [Co(NH 3 ) 6 ]ClÁSiF 6 Á2H 2 O. The crystal lattice consists of discrete ions, [Co(NH 3 ) 6 ] 3+ , SiF 6 2À and Cl À and two water molecules.…”

“…It is stabilized by extensive hydrogen bonding besides electrostatic forces. We have already reported hexaamminecobalt(III) salts with inorganic oxo-anions [10][11][12] and organic oxo-anion [13].…”