0000000000026408
AUTHOR
Jean-yves Salaün
New Multidimensional Coordination Polymers with μ 2 ‐ and μ 3 ‐dcno Cyano Carbanion Ligand {dcno – = [(NC) 2 CC(O)O(CH 2 ) 2 OH] – }
New polymeric materials [M(dcno)2(H2O)2] [M = FeII (1), CoII (2)] and [M(dcno)2] [M = CuII (3), MnII (4)] with dcno– =[(NC)2CC(O)O(CH2)2OH]– = 2,2-dicyano-1-(2-hydroxyethoxy)ethenolate anion have been synthesised and characterised by IR spectroscopy, X-ray crystallography and magnetic measurements. In compounds 1 and 2, each organic ligand acts in a bridging mode with its two nitrogen atoms bound to two different metal ions, while in compounds 3 and 4, each organic anion acts as a μ3-bridging ligand through its two nitrogen atoms and the oxygen atom of the OH group. Each metal ion has a pseudo-octahedral trans-MN4O2 environment with four nitrogen atoms from four different organic ligands an…
New planar polynitrile dianion and its first coordination polymer with unexpected short M⋯M contacts (tcno2−=[(NC)2CC(O)C(CN)2]2−)
International audience; A new planar polynitrile dianion ([tcno]2− = [(NC)2CC(O)C(CN)2]2−) has been synthesized as its potassium salt, K2[tcno] (1). The crystallization of 1 by the slow evaporation of an aqueous solution at room temperature gave two types of colourless crystals having two different shapes [1-A: fine plates and 1-B: needles] for which the crystal structure determinations showed similar geometries for the polynitrile anion in both the structures. The combination of this novel dianion with Cu(II) led to the coordination complex [Cu(tcno)2(H2O)2] (2), which constitutes the first coordination complex of this dianion. The structure of 2 can be described as a coordination polymer …
Effects of substitutions on cyclopentadienyl rings in complexes with molybdenum-mercury bonds. 95Mo and 199Hg NMR studies
NMR data for 95Mo and 199Hg nuclei have been obtained for new di- and trimetallic complexes Cp′(CO)3MoHgX containing molybdenum-mercury bonds and bulky and/or potentially bifunctional substituted cyclopentadienyl ligands; Cp′=C5HMe2Ph2, C5Me4Bz, C5Bz5, C5H4PPh2 and C5Me4PPh2 (Bz=CH2C6H5; Me =CH3; Ph=C6H5); X=Cp′(CO)3Mo, Cl, Br, 1, SCN. They are discussed within the context of our earlier results reported for analogous complexes with the cyclopentadienyl ligands bearing methyl groups. With the exception of phenyl substituted rings, a rather narrow range of 95Mo chemical shifts is found for the compounds with the same number of different substituents on cyclopentadienyl ligands. An outstandin…
Cyclization of the pyruvyl(methoxycarbonyl)tetracarbonyliron complex cis-(CO)4Fe[C(O)C(O)CH3](CO2CH3) induced by pronucleophile reagents
International audience; Two iron complexes, cis-(CO)4Fe[C(O)C(O)CH3](CO2CH3) (1a) and cis-(CO)4Fe[C(O)CO2-CH2] [C(O)CH2] (3), are reported. Each complex can be considered as a λ-keto ester with a metal atom inserted into the chain linking its two organic groups. 1a is the only one found to evolve thermally, similarly to organic λ-keto esters, into the methoxy metallalactone (CO)4FeC(O)C(CH3)(OCH3)OC(O) (2a). This reaction is not reversible and does not require any acid or alkaline catalysis. The process does not result from a spontaneous dissociation of the methoxycarbonyl ligand of la but from an associative intra or intermolecular mechanism. A similar process can also be induced by pronuc…
New coordination polymer based on a triply bridged dicarboxylate ligand: Synthesis, structure, and magnetic properties of the adipato complex [Cu4(bpy)4(adip)3](tcnoet)2·2H2O {bpy=C10H8N2; adip2−=[O2C(CH2)4CO2]2−; tcnoet−=[(NC)2CC(OEt)C(CN)2]−}
International audience; One-pot reaction of copper(II) chloride dihydrate CuCl2 · 2H2O with 2,2′-bipyridyl (bpy = C10H8N2) in the presence of sodium adipate Na2adip (adip2− = [O2C(CH2)4CO2]2−) and potassium 1,1,3,3-tetracyano-2-ethoxypropenide (tcnoet− = [(NC)2CC(OEt)C(CN)2]−) gives the new compound [Cu4(bpy)4(adip)3](tcnoet)2 · 2H2O (1), which was characterized by single crystal X-ray diffraction analysis. The Cu(II) metal ion presents an elongated square pyramidal CuN2O3 environment, with an oxygen atom in apical position and a base plane involving almost equivalent bond lengths. The structure can be described as a pseudo dinuclear species in which two Cu(bpy) units are triply bridged by …
A novel polynitrile ligand with different coordination modes: Synthesis, structure and magnetic properties of the series [M(tcnoprOH)2(H2O)2] (M=Mn, Co and Cu) (tcnoprOH−=[(NC)2CC(OCH2CH2CH2OH)C(CN)2]−)
International audience; A novel polynitrile ligand (tcnoprOH− = [(NC)2CC(OCH2CH2CH2OH)C(CN)2]−) with up to five potentially coordinating groups has been synthesized in a one-pot reaction from a cyclic acetal and malononitrile. The combination of this novel ligand with different transition metal ions has led to the synthesis of two different structural types with the same formula but with different coordination modes in the ligand. Mn(II) and Cu(II) lead to a μ2-N,O-coordinating mode in the series of compounds formulated as [M(N,O-tcnoprOH)2(H2O)2] (M = MnII (1) and CuII (2)), whereas Co(II) and, most probably Ni(II), lead to a μ2-N,N′-coordinating mode in [Co(N,N′-tcnoprOH)2(H2O)2] (3). Bot…