Crystal structure of diaquadichloro(1,10-phenanthroline)chromium(III) chloride dihydrate, [CrCl2(C12H8N2)(H2O)2]Cl ·2H2O

Abstract

Source of materialAsolution of phenanthroline (phen, 90 mg, 0.5 mmol) in 10 ml ethanol was slowly added to asolution of CrCl 3 ·6H 2 O(133 mg, 0.5 mmol) in 30 ml water. The reaction mixture was stirred for 3 hours with refluxing and then filtered. The resulting blue filtrate was allowed to stand at room temperature. After two weeks, gray prism-shaped crystals suitable for X-ray analysis were obtained. Experimental detailsAll the hydrogen atoms of the water molecules were found in difference Fourier maps. And the other Hatoms were treated as riding-model for phenanthroline with alkylene d(C-H) =0.93 Å, and their U iso =1.2U eq (carrier atom). DiscussionChromium complexes containing phenanthroline (phen) were rarely reported compared to that of other transitional metals, and most of chromium complexes were concerned because of their magnetic properties [1][2][3]. The title complex has been synthesized in aconvenient approach previously [4] and its bioactivity was investigated, but no crystal structural characterization was reported in the literature [5]. Astructure of chromium complex coordinated by phen, H 2 Oand Cl − together has not been reported yet, and the other transitional metal complexes with the similar composition to the title complex were also seldom reported [6][7][8][9] + cation possesses a C 2v symmetry, in which the central chromium ion adopts a trans-octahedral coordination CrN 2O2Cl2 with two Natoms of phen and two Oatoms of coordinate waters locating at equatorial planeand two Cl − anions occupying two apical positions. The Cr-N, Cr-Cl and Cr-O bond length with 2.059(2), 2.3160(8) and 1.975(2) Å,respectively, are close to those in the similar chromium complexes [10,11]. The Cl − acts as acounter anion and plays an important role in the formation of hydrogen-bonded two-dimensional network. Each Cl − ion links two coordinate and two crystal waters with O1-H1A···Cl2 [3.024(2) Å,160(3)°] and O2-H2B···Cl2 [3.208(3) Å,102(4)°], respectively, resulting in four O-H···Cl hydrogen bonds. There are also O1-H1B···O2 [2.617(3) Å, 180(4)°] hydrogen bonds between the coordinate and crystal waters, which connect the cations and crystal waters to at wodimensional layer structure together with O-H···Cl hydrogen bonds ( figure, bottom). The phen ligands lie the both sides of the layer shaped as hackle. The two-dimensional layers are further aggregated by the p-p packing interaction between the phen ligands from the adjacent layers, resulting in at hree-dimensional supramolecular structure.

Biphasic oxidation of diaquadichloro(1,10‐phenanthroline)chromium(III) by N‐bromosuccinimide and the formation of chromium(IV) and chromium(V)

“…In Equation (2), A is the Cr(III) complex, B the intermediate Cr(IV) complex, and C is the final Cr(V) product of the reaction. Equation (3) is used for the determination of the two rate constants of a biphasic reaction 10–14 . In this equation, x is the independent variable (time), 1/ t 1 = k f and 1/ t 2 = k s , the pseudo first order rate constants for the fast and the slow reactions, respectively.…”

“…The [Cr III Cl 2 (phen)(H 2 O) 2 ]Cl⋅2H 2 O complex was prepared according to the literature method 14 . The product of the reaction was isolated by reacting 1:2 mol ratios of the of Cr(III) complex:NBS.…”

“…The [Cr III Cl 2 (phen)(H 2 O) 2 ]Cl⋅2H 2 O complex was prepared according to the literature method. 14 The product of the reaction was isolated by reacting 1:2 mol ratios of the of Cr(III) complex:NBS. The absorption spectrum of the of an aqueous solution of the chromium(III) complex in 0.10 M HNO 3 was recorded over the 400-800 nm wavelength range.…”

“…Equation ( 3) is used for the determination of the two rate constants of a biphasic reaction. [10][11][12][13][14] In this equation, x is the independent variable (time), 1/t 1 = k f and 1/t 2 = k s , the pseudo first order rate constants for the fast and the slow reactions, respectively. The values of k f and k s are obtained using an Origin 9 software program for consecutive first order reactions.…”

Kinetics and mechanism of the one‐step, two‐electron oxidation of diaquadichloro(1,10‐phenanthroline)chromium(III) chloride dihydrate by periodate to chromium(V) in aqueous acidic solutions

“…The complex [Cr III Cl 2 (phen)(H 2 O) 2 ]Cl⋅2H 2 O (phen = 1, 10‐phenanthroline) was synthesized by a method similar to that reported in the literature 26 . The isolated chromium(III) complex in 0.1 M HNO 3 aqueous solution has an absorption maximum at 589 nm.…”