Octahedral and Tetrahedral Cobalt(II) Sites in Cobalt Chloride Complexes with Polyethers

Abstract

Abstract. A reaction of cobalt chloride hexahydrate with dimethoxyethane (dme) resulted in a dinuclear complex [CoCl 2 (dme)] 2 (1). The complex 1 reacted with di(2-methoxyethyl) ether (diglyme) in tetrahydrofuran (thf) solvent achieving polymeric [Co 2 Cl 4 (diglyme)] n (2). A reaction of cobalt chloride hexahydrate, diglyme and (CH 3 ) 3 SiCl in thf yielded the crystals of [Co 2 Cl 4 (diglyme)(thf)] (3). Both, tetrahedral and octahedral environments of cobalt ions were found in each of the complexes, 1, 2 and 3. Cobalt ions display a distorted octahedral geometry with bridging chlorides and terminal oxygen atoms from ether ligands and a distorted tetrahedral geometry with non-bridging and bridging chlorides. A four-and a sixcoordinate cobalt ion are linked by a double chloride bridge in the dinuclear complexes 1 and 3. Two tetrahedral or two octahedral cobalt ions in 2 are connected by double chloride bridges in dinuclear units which are linked to infinite chains by single chloride bridges. (doi: 10.5562/cca1747)

Syntheses and crystal structures of vanadium and iron chloride complexes with diglyme

“…A chelate η 3 , non-bridging coordination of diglyme as characteristic for all complexes of the first row d-block metals [13][14][15][16] was found in the four novel vanadium and iron complexes 1-4. The new complex of vanadium(III) chloride with diglyme 1 is a mononuclear compound with a facial arrangement of O-donor atoms from diglyme, which has been already reported for [MCl 3 (diglyme)] (M = Sc, Ti).…”

“…[5][6][7][8][9][10] On the other hand, only a few examples of the first row d-block metal halide complexes with diglyme were prepared. They are either mononuclear molecular [MCl 3 (diglyme)] (M(III) = Sc, Ti), [11][12] [MX 2 (diglyme)] (X = Cl, M(II) = Zn, X = I, M(II) = Co, Zn) complexes, [13][14] dinuclear [MX 2 (diglyme)] 2 (X = Cl, M(II) = Mn, Co, Ni; X = Br, I, M(II) = Ni) or 1-D polymeric [Co 2 Cl 4 (diglyme)] n . [13][14][15][16] Metal M(II) ions in polymeric and dinuclear complexes are connected by halides to achieve a preferred octahedral environment.…”

“…They are either mononuclear molecular [MCl 3 (diglyme)] (M(III) = Sc, Ti), [11][12] [MX 2 (diglyme)] (X = Cl, M(II) = Zn, X = I, M(II) = Co, Zn) complexes, [13][14] dinuclear [MX 2 (diglyme)] 2 (X = Cl, M(II) = Mn, Co, Ni; X = Br, I, M(II) = Ni) or 1-D polymeric [Co 2 Cl 4 (diglyme)] n . [13][14][15][16] Metal M(II) ions in polymeric and dinuclear complexes are connected by halides to achieve a preferred octahedral environment. A great flexibility of diglyme is most clearly demonstrated in complexes with octahedral arrangement of donor atoms coordinated to M 2+ or M 3+ either in mer or fac geometry (Chart 1).…”

“…[11][12] Dinuclear octahedral M(II) complexes (M = Mn, Co, Ni and Mg) with bridging halides and coordinated diglyme crystallize as mer isomers. [13][14][15][16][17] Mononuclear scandium(III) and titanium(III) chloride complexes with diglyme crystallize as fac isomers, [11][12] and a complex of a smaller 18 Al 3+ is the mer-[AlBr 3 (diglyme)]. 19 We prepared vanadium and iron chloride complexes with diglyme to continue our investigation of nuclearity and isomerism in the first row d-block metal halide complexes with this polyether.…”

“…All three oxygen atoms, O1, O2, O3, of diglyme and the central metal atom M are almost in the same plane with O1-M-O3 angles in the range from 144 to 156 o in mer isomers. [13][14][15][16][17] In fac isomers are the two planes, each through the central metal atom M, the middle (O2) and one of terminal oxygen atoms (O1 or O3) in diglyme, nearly perpendicular to each other with O1-M-O3 angles close to 90 o . [11][12] Dinuclear octahedral M(II) complexes (M = Mn, Co, Ni and Mg) with bridging halides and coordinated diglyme crystallize as mer isomers.…”