A novel type of tetranuclear cluster with the trinucleating ligand 1,2-Bis(benzimidazol-2-yl)-1-hydroxyethane. Crystal and molecular structure of Ni(HRSL)2(CF3SO3)2 and [Cu4(SL)4(NO3)2(EtOH)] (NO3)2(EtOH)3(H2O)2; spectroscopy and magnetism of these and related transition metal compounds

Dinuclear Complexes Formed by Hydrogen Bonds: Synthesis, Structure and Magnetic and Electrochemical Properties

“…Mn II Mn III MnÀN ax 2.226 (5) 2.277(4) 2.237 (5) 2.288(4) MnÀN eq 2.209 (5) 2.030(4) 2.215 (5) 2.038 (5) MnÀO2.184 (5) 1.905(4) 2.250 (5) 1.916(4) MeanM ÀL2.220 2.076 althoughs lightly greatert han for the M II M II complexes, are still much shortert han the normal distance around2 .75 .T he electrochemistry discussed below indicates strongly that the dimers persist in solution in polar solvents. The coordinationo ft he metal ions is essentially the same in all complexes.T he ligands bind with the six-membered chelate ring in the N 2 O 2 plane and the five-membered chelate rings perpendicular to this plane.A ll complexes have ac rystallographic or non-crystallographic two-fold symmetry axis bisecting the O-M-O angle.…”

“…Species A hasb een observed as trans isomers [8] and by Reedijk and co-workers as a cis isomer with nickel(II). [5] Species B and C have been characterisedb yX -ray crystallography and the transformation of A into B was shown by potentiometry. D has been characteriseds tructurally as a trans isomer with Co III [8] and its existence has been shownb yp otentiometry and the ion has been observed by ESI-MS for cobalt(III), manganese(III) and iron(III).…”

“…We have previously studied this ligand in connection with the formation of tetranuclear cubanes where the alcohol functioni sc ompletely deprotonated and acts as at riply bridging ligand. [4] The nonmethylated form of 1 has been studied by Reedijk [5] and we have studied mononuclear [6] and cubane [7] complexes of the related ligand 2 (Scheme 1) derived from tartaric acid. We were interested to examines imple complexes of the type [M(1) 2 ] n + where the ligandsa cts as at ridentate facially coordinating ligand,a nd in the course of this work discovered the dimers that are the subjecto ft his work.…”

Coordination Chemistry of the Chiral, Facially Coordinating Tridentate Ligand 1,2‐Bis(benzimidazol‐2‐yl)ethanol with 3d Transition Metals

“…Another reported a structure for the complex [Co( 1 )Cl 2 ] where the ligand is bidentate, using only the nitrogen donors . The Reedijk group reported the formation of a copper cubane, and later reported a dinuclear copper species . We have previously studied the use of 1 and 2 in cubane complexes .…”

“…The related ligand 3 prepared from tartaric acid has attracted more attention from us and other groups, but the additional alcohol function can lead to a diversity of coordination modes (Scheme ) . The simplest complex one can imagine for this tridentate ligand is an octahedral complex of composition ML 2 , but only one such complex has been reported, a complex of nickel(II) …”