V. I. Pavlovskii

Photochemical decarboxylation and deacetylation of the cobalt(III) aminocarboxylate complexes: The crystal structure of the [Co(CH2CH2CH2NH2)(En)2)]Br2 and [Co(Bipy)(Cl)(Edma)]Cl · 2H2O photoproducts (En is Ethylenediamine, Bipy is 2,2′-bipyridine, and Edma is ethylenediaminemonoacetate)

The crystals of [Co(CH2CH2CH2NH2)(En)2]Br2 (I) and [Co(Bipy)(Cl)(Edma)]Cl · 2H2O (IIa) (IIa) are studied by X-ray diffraction analysis. Compound I is synthesized by the crystallization of the [Co(En)2(Amb)]2+ primary photolysis products. Compound IIa is synthesized from the [Co(Bipy)(Edda)]+ final photolysis products (En is ethylenediamine; Bipy is 2,2′-bipyridine; Edma and Edda are the anions of ethylenediaminemonoacetic and ethylenediamine-N,N′-diacetic acids, respectively; Amb is the 4-aminobutyrate ion). The crystal structure of complex I indicates the contraction of the seven-membered aminobutyrate CoO2CCH2CH2CH2NH2 ring to the five-membered CoCH2CH2CH2NH2 ring by the photoelimination of the CO2 molecule. The formation of the Co(III) complexes with the Edma ligands upon the photolysis of [Co(Bipy)(Edda)]+ is due to successive reactions of contraction of the five-membered aminoacetate rings and hydrolysis of the Co-C bond.

Crystal structure of barium α-(Ethylenediamine-N,N-diacetato)malonatocobaltate(III) perchlorate pentahydrate Ba[Co(Edda)(Mal)(ClO4) · 5H2O

AbstractThe crystal structure of [Co (Edda)(Mal)](ClO4) · 5H2O is determined by X-ray diffraction analysis (the crystals are triclinic: a = 10.1363(12) Å, b = 11.0801(13) Å, c = 11.3173(13) Å, α = 101.129(13)°, β = 108.594(13)°, γ = 112.883(13)°, Z = 2, space group P

Synthesis, structure, and photodecarboxylation of cobalt(III) complexes with diethylenetriamine and L-ornithine [Co(Dien)(Orn)](ClO4)2 · 0.5H2O or DL-histidine [Co(Dien)(His)](ClO4)2

\overline 1

The heterometallic two-dimensional structure in the Ba2[Cu(L)](ClO4)2 · nH2O crystals (L = ethylenediaminetetraacetate, n = 6; L = ethylenediaminetetra-3-propionate, n = 5)

). The Co3+ ion coordinates two O atoms of the malonate ion, as well as two N atoms and two trans-O atoms of the ethylene-N,N-diacetate ion. The [(H2O)4Ba(ClO4)]+ subunits interact with the [Co(Edda)(Mal)]− complexes to form infinite ribbons, and each complex is bonded with three Ba atoms through the O atoms of the carboxyl groups. The coordination number of the Ba atom is nine (four O atoms of the water molecule, one O atom of the perchlorate ion, and four O atoms of three adjacent complexes).

Crystal structure of barium (cyclohexane-1,2-diaminetetraacetato)cobaltate(III) nonahydrate Ba[Co(Cdta)]2 · 9H2O

Abstract[Co(CN)2(H3Cdta)] · 2H2O (I) and Na2[Co(CN)(Cdta)] · 3H2O (II) (Cdta4− is the 1,2-cyclohexanediaminetetraacetate) were synthesized. In I, the two cyanide ions and the Cdta nitrogen atoms are located in the equatorial plane, the carboxyl groups connected to different N atoms are in axial positions; in addition one of them, like two other uncoordinated carboxyl groups, is protonated. In II, Cdta is a pentadentate ligand coordinated in the cis-equatorial mode. UV excitation of the dicyano complexes at the ligand-to-metal charge transfer band gives organic derivatives of cobalt(III) stable enough for chromatographic isolation. Photolysis of II in neutral medium gives aqua(cyclohexanediaminetriacetato)cobalt (III) complexes as the final products.

Crystal structure of barium trans(O)-cis(CN)-Bis(2-picolinato)dicyanocobaltate(III) hydrate [Ba(H2O)4][Co(Pic)2(CN)2]2 · 4.41H2O

Mixed cobalt(III) complexes with diethylenetriamine (Dien) and a tridentate anion of L-ornithine (Orn) [Co(Dien)(His)](ClO4)2 · 0.5 H2O or DL-histidine (His) [Co(Dien)(Orn)](ClO4)2 are synthesized. According to the X-ray diffraction studies, the secondary N atom of diethylenetriamine is trans to the donor N atom of the side chain of the amino acid. Organometallic products of photodecarboxylation of the complexes are isolated by ion exchange chromatography. The electronic absorption spectra indicate that the products contain three-membered Co-C-N rings.

Crystal structure of tris(ethylenediamine)cobalt(III) (aqua)hexachloromercurate(II) chloride [Co(En)3]2[Hg2(H2O)Cl6]Cl4

Crystals of Ba[Co(Nta)(C2O4)] · 3H2O were prepared, and their structure was solved by X-ray diffraction (monoclinic space group P21/c), a = 10.0111(10) Å, b = 10.2838(6) Å, c = 14.2748(15) Å, ß = 100.350(12)°, Z = 4). The local environment of a Ba2+ ion includes two O atoms of water molecules and seven O atoms of the carboxyl groups of Nta3− and C2O42− ions of five complex anions. Honeycomb type layers can be distinguished in the crystal lattice; within the layers, each Ba2+ atom interacts with three complexes and vice versa. In addition, each Ba atom of the layer is bonded to complexes of the upper and lower layers. Thus, the crystal represents a three-dimensional coordination polymer.

Crystal structures of calcium and barium oxalato(ethylenediamine-N,N′-diacetato)× chromates(III) M[Cr(Edda)(C2O4)]2·5H2O (M = Ca, Ba)

The crystals of Ba2[Cu(Edtp)](ClO4)2 · 5H2O (i) contain the tetragonal-pyramidal complexes of Cu(II) with ethylenediaminetetra-3-propionate ion with one noncoordinated propionate group. The [Cu(Edtp)]2− complex ions and two sorts of the Ba atoms form two-dimensional supramolecular aggregate. Two Ba(1) atoms and one Cu atom form a tetramer by means of the coordinated carboxyl group and a free propionate group. The tetramers are united through the propionate group into ribbons, which are joined by the Ba(2) atoms into the layers. The coordination sphere of each B atom involves four water molecules, including two bridging water molecules. The perchlorate ions are also coordinated by the Ba atoms, one Ba atom acting as a bridge. The structure of the previously studied Ba2[Cu(Edta)](ClO4)2 · 6H2O (II) crystals with the hexadentate ethylenediaminetetraacetate ion is shown to be similar to that of complex I, but in the case of II, the Ba atoms are equivalent as regards the number of the complex anions bound to them.