Novel Alkoxide Cluster Topologies Featuring Rare Seesaw Geometry at Transition Metal Centers

Abstract

Caution! Chemists playing: Novel clusters of the form [M2Li2Cl2(OR)4] featuring rare seesaw geometry at the transition metal centers were synthesized for M=Cr-Co. The use of sterically hindering alkoxide ligands, as well as the inclusion of lithium ions in the structures enforces this highly unusual configuration.

CuIIGdIII Cryogenic Magnetic Refrigerants and Cu8Dy9 Single‐Molecule Magnet Generated by In Situ Reactions of Picolinaldehyde and Acetylpyridine: Experimental and Theoretical Study

“…To our knowledge, this strange coordination geometry (CN = 4, seesaw) is the first reported case for Cu II , though it is relatively common for Cu I and extremely rare for other transition metals. [21] We believe that the various co-ordination geometries in complexes 1-3 help the assembly of different cluster topologies of [Ln x Cu y ].…”

A selective detection approach for copper(ii) ions using a hydrazone-based colorimetric sensor: spectroscopic and DFT study

“…The DFT search for the minimum form of the Ni complex showed an appreciable steric repulsion between the two ligand molecules coordinated to the metal ion center, resulting with the least stable binding among the three metal ions. While the seesaw configuration has less experimental evidences in coordinated compounds of zinc and copper, 48–51 it is expected to avail a more stable binding state with the ligand compared to the square planar Ni(3-HNHBH) 2 2+ metal complex ( Table 1 ). Moreover, while the complexation with Zn( ii ) ions was predicted to exhibit a relatively higher binding affinity followed by Cu then Ni, careful inspection of the calculated geometrical parameters and the qualitative overview of the structure ( Fig.…”

Catalytic synthesis of azoarenes via metal-mediated nitrene coupling

“…65 Furthermore, π donation from an alkoxide ligand can compete with the π-donation from the imido group, decreasing the multiple MvNR bond character and increasing its group transfer reactivity. Groysman, Lord, and coworkers have synthesized series of well-defined Cr(II)-Co(II) transition metal complexes with bulky alkoxide ligand OR (OR = OC t Bu 2 Ph), 66,67 and explored their reactivity in group-transfer reactions. 37,68 Mononuclear M(OR) 2 (THF) 2 precursors (M = Mn, Fe, Co) complexes exhibited geometry intermediate between tetrahedral and seesaw, featuring wide interalkoxide angle (130-139°), and narrow angle between THF ligands (83-88°).…”