Synthesis, Spectroscopic and X-ray Structural Study ofcis-diazidobis- (ethylenediamine)Cobalt(III) Thiocyanate

Abstract

Reaction of cis-diazidobis(ethylenediamine)cobalt(III)nitrate with ammonium thiocyanate in a 1 : 2 molar ratio in aqueous medium gave the title cobalt(III) compound, cis-[Co(en) 2 (N 3 ) 2 ]SCN, as reddish brown crystals in almost quantitative yield. The complex salt was characterized by elemental analysis, IR, electronic, 1 H and 13 C NMR spectroscopic studies. An X-ray structure determination revealed an ionic structure with the monoclinic space group P2 1 /c, having cell dimensions a ¼ 12.1950(6), b ¼ 9.0317(5), c ¼ 12.6017(7) Å ; ¼ 113.419 (1) , V ¼ 1273.63(12) Å 3 and Z ¼ 4. The structure was refined by a full-matrix least-square procedures to R 1 ¼ 0.0297 and wR 2 ¼ 0.0697.

Cationic Cobaltammines as anion receptors: a convenient synthesis, characterization and X-ray structure of [CO(NH3)6]ClSeO4·3H2O

“…The hexaamminecobalt(III) cation has proved very useful as a large counter ion in stabilizing [15] [18][19][20][21][22][23][24] of our interest in cobalt(III) complex salts.…”

Synergistic cation-to-anion and anion-to-cation interactions in the binding of oxoanions: Syntheses, characterizations, and single-crystal structures of [Co(phen)2CO3]ClO3, [Co(phen)2CO3]BrO3·3.5H2O and [Co(phen)2CO3]IO4

“…These values are significantly smaller than those of typical 1:1 strong electrolytes [9] but comparable to those of some other cobalt(III) complex salts, e.g. K o = 70 S cm 2 mol À1 for [cisCo(en) 2 (N 3 ) 2 ](C 9 H 11 SO 3 ) [10] and K o = 51 S cm 2 mol À1 for [cisCo(en) 2 (N 3 ) 2 ]SCN [11]. The decrease in K o values could be ascribed to ion-pair formation.…”

Second-sphere coordination in anion binding:cis-diazidobis(ethylenediamine-κ2N,N′)cobalt(III) picrate

“…We are currently engaged in studies to explore cobalt(III) complexes as potential anion receptors and have previously reported the crystal structures of some cis-diazidobis(ethylenediamine)cobalt(III) salts (Sharma et al, 2003). The [cis-Co(N 3 ) 2 (en) 2 ] + cation (en is ethylenediamine) has also been characterized as a nitrate salt (Padmanabhan et al, 1968;Kastner et al, 1989).…”