Alcoholysis/hydrolysis of 1,1′-carbonyldiimidazole as a means of preparing unprecedented, imidazole-containing one-dimensional coordination polymers of copper(II)

Abstract

The use of 1,1'-carbonyldiimidazole, (im)(2)CO, for the synthesis of imidazolate (im(-)) and/or imidazole (Him)-containing copper(II) coordination polymers is described. The [Cu(2)(O(2)CMe)(4)(H(2)O)(2)]/(im)(2)CO reaction system in EtOH yields the new polymeric species [Cu(O(2)CMe)(im)(Him)(EtOH)](n) () and the known compound [Cu(im)(2)](n) (), depending on the reaction conditions. A mechanism for the alcoholysis/hydrolysis of (im)(2)CO is proposed. Complex comprises neutral, zigzag chains with the eta(1):eta(1):mu im(-) ligand bridging two neighbouring Cu(II) atoms. Each square pyramidal metal centre is coordinated to two imidazolate nitrogen atoms, the pyridine-type nitrogen atom of the terminal imidazole ligand, one acetate oxygen atom and the ethanol oxygen atom. The dc magnetic susceptibility data for have been analysed according to the Bonner-Fisher model for an equally spaced S = 1/2 chain, revealing moderate antiferromagnetic Cu(II)Cu(II) exchange interactions (J = -33.5 cm(-1) using the H = -2J summation operatorS(i)S(i+1) spin Hamiltonian). The reaction system Cu(NO(3))(2).3H(2)O/(im)(2)CO in EtOH leading to the preparation of known trans-[Cu(NO(3))(2)(Him)(4)] () is also described. With terephthalate(-2) (tp(2-)), instead of MeCO(2)(-), in MeOH/H(2)O the product is the new, 1D linear coordination polymer [Cu(tp)(Him)(2)(H(2)O)](n).2nH(2)O (.2nH(2)O). Adjacent square pyramidal Cu(II) atoms are singly bridged by the bis-monodentate tp(2-) ligand, while two monodentate Him groups and one H(2)O molecule complete five-coordination at each metal centre. The chains of and .2nH(2)O form interesting, hydrogen-bonded 3D networks. The combined work demonstrates the usefulness of (im)(2)CO in the preparation of interesting Cu(II) coordination polymers which can not be obtained by the use of Him.

An Imidazolate‐ and Azide‐Bridged Copper(II) Coordination Polymer Consisting of Alternating Di‐ and Mononuclear Units

“…In a recent study with approximately the same φ angle (φ = 163.8°), a J value of -34 cm -1 was reported. [24] Thus, it was estimated that J 2 and J 2 Ј are moderate and it was assumed that J 2 ≈ J 2 Ј. From the above considerations, the present system could be simplified to two types of exchange interactions with opposite signs (J 1 Ͼ 0, J 2 Ͻ0 and J 1 Ͻ |J 2 |) that are alternately arranged along the one-dimensional direction.…”

“…Thirdly, the exchange interactions through the im bridges are usually antiferromagnetic with J values of -88 to 0 cm -1 . [24,45] The important struc-tural parameter affecting J is the Cu-N im ···N im angle (φ), where when φ is 180°, J is at the maximum value. In the im bridge between the D and the M units, the average φ value for Cu1-N3-N4 and Cu2-N4-N3 is 161.8°, while the corresponding value for the im bridge between the DЈ and the M units is 159.0°.…”

“…[19] However, Him/im-based coordination polymers are not very numerous, [20][21][22][23][24][25][26] probably due to the lack of structural information resulting from the difficulty of growing single-crystals. In practice, recent successful syntheses have been achieved by using superior methods such as the hydrothermal synthesis, [22,23] the solvolysis of carbonyldiimidazole [24,25] and synthesis using ionic liquid. [26] Structurally simple ligands such as azide and Him/im are expected to provide novel coordination polymers with both topological and magnetic diversity.…”

Current Developments in the Syntheses of 1,2,4-Triazole Compounds

“…This reaction provides a practical synthetic route for the preparation of triazole adamantanes with large steric hindrance to overcome the serious amantadine/rimantadine resistance of influenza viruses. Thionyl bis-triazole can also be employed to N-alkylate with alcohols to produce novel triazole derivatives [242,243]. Reaction between compound 170 and N,N -thionylditriazole 171 successfully afforded potential CYP26 inhibitor 1,2,4-triazole derivative 172 (Scheme 71) [244].…”

Investigating the isolation and interconversion of two diastereoisomers in an octahedral system

“…First, this molecule normally behaves as a neutral, O,N-bidentate chelating ligand, 9,10 (exceptions are known, [11][12][13][14] Scheme 2) and, second, it can undergo impressive metal ionassisted transformations, 15,16 a topic that is currently one of the central themes in our research efforts. [17][18][19] Treatment of NiCl 2 Á6H 2 O with (py)(ph)CO (1 : 2) in EtOH gave an olive green solution from which were subsequently isolated dark orange-red crystals of trans,trans,trans-[NiCl 2 {(py)-(ph)CO} 2 ]Á0.4H 2 OÁ0.6EtOH (1Á0.4H 2 OÁ0.6EtOH) in moderate yields (50-55%) upon vapour diffusion with Et 2 O. The 1 : 2 reaction between NiCl 2 Á6H 2 O and (py)(ph)CO (1 : 2) in MeCN gave a green solution from which were subsequently isolated green crystals of cis,cis,trans-[NiCl 2 {(py)(ph)CO} 2 ] (2) in rather high yields (B70%) upon liquid diffusion with Et 2 O.…”