Dimanganese(III) complexes of salen-type ligands anchored by 9,9-dimethylxanthene-4,5-diyl spacers were synthesized. Two types of structures, cyclic and acyclic forms, are presented. The 2 + 2 Schiff-base condensation of 5,5′-(9,9-dimethylxanthene-4,5-diyl)bis(salicylaldehyde) and 1,2-diaminobenzene gave a macrocyclicligand, from which a cyclic dimanganese(III) complex was synthesized. A similar dimanganese(III)
A tetranuclear nickel cluster isolated in multiple high-valent states
作者:Samuel I. Jacob、Iskander Douair、Guang Wu、Laurent Maron、Gabriel Ménard
DOI:10.1039/d0cc01699c
日期:——
We report a series of high-valent tetranuclear nickel clusters isolated from the chemical oxidation of an all Ni(II) ([Ni4]) neutral cluster. Electrochemical analysis of [Ni4] reveals three reversible sequential oxidations at 0.248 V (1e−), 0.678 V (1e−), and 0.991 V (2e−) vs. Fc/Fc+ corresponding to mono-, di-, and tetra-oxidized species, [Ni4]+, [Ni4]2+, [Ni4]4+, respectively. Using spectroscopic
Tetra- and dinuclear manganese complexes of xanthene-bridged O,N,O-Schiff bases with 3-hydroxypropyl or 2-hydroxybenzyl groups: ligand substitution at a triply bridging site
[Mn4(L1)2(μ-OAc)2] was converted to the oxo-bridged tetramanganese(III,III,III,III) complex [Mn4(L1)(HL1)(μ3-O)(μ-OAc)2]+ by treating with NH4PF6 or NH4BF4: a triply bridging alkoxide was protonated and replaced by an oxide ligand. The cyclic voltammograms of [Mn4(L1)(HL1)(μ3-O)(μ-OAc)2]+ suggested that the reverse reaction forming [Mn4(L1)2(μ-OAc)2] occurred in the electrochemical processes and was assisted by protonation
U形配体L 1和L 2是5,5'-(9,9-二甲基x吨-4,5-二基)双(水杨醛)(H 2黄醛)的席夫碱的配位性质研究了-1-丙醇或2-羟基苄胺分别构建多核锰配合物。在这些配体中,两个O,N,O-席夫碱被a吨骨架桥接。H 4 L 1或H 4 L 2与锰盐的反应提供了四核和双核锰配合物,包括四锰(II,II,III,III)配合物[Mn 4(L 1)2(μ-OAc)2 ]的Mn 4 O 6核表现出不完全的双库仑结构。在Mn 4 O 6核中,酚盐和醇盐O原子桥接锰离子。去质子化的3-羟丙基对四个锰离子的组装至关重要,因为在不存在碱的情况下获得了酚盐桥联的二锰(III,III)络合物[Mn 2(H 2 L 1)2 ] 2+。4 L 2,其在H 4中具有2-羟苄基而不是3-羟丙基L 1,得到环状二锰(IV,IV)配合物[Mn 2(L 2)2 ]。我们公开了[锰4(L 1)2(μ-OAC)2 ]转化