Synthesis of Azoimidazolium Dyes with Nitrous Oxide
作者:Alexander G. Tskhovrebov、Lara C. E. Naested、Euro Solari、Rosario Scopelliti、Kay Severin
DOI:10.1002/anie.201410067
日期:2015.1.19
method for the synthesis of industrially important azoimidazoliumdyes is presented. The procedure is based on a reagent which is rarely used in the context of synthetic organic chemistry: nitrousoxide (“laughing gas”). N2O is first coupled to N‐heterocyclic carbenes. Subsequent reaction with aromatic compounds through an AlCl3‐induced CH activation process provides azoimidazoliumdyes in good yields
Delivery of a Masked Uranium(II) by an Oxide‐Bridged Diuranium(III) Complex
作者:Dieuwertje K. Modder、Chad T. Palumbo、Iskander Douair、Farzaneh Fadaei‐Tirani、Laurent Maron、Marinella Mazzanti
DOI:10.1002/anie.202013473
日期:2021.2.15
In particular, the UIII/UIII oxide complex effects the reductive coupling of pyridine and two‐electron reduction of 4,4′‐bipyridine affording unique examples of diuranium(III) complexes bridged by N‐heterocyclic redox‐active ligands. These results provide insight into the chemistry of low oxidation state metal oxides and demonstrate the use of oxo‐bridged UIII/UIII complexes as a strategy to explore
氧化物是用于构建多金属配合物的引人注目的连接物,可提供金属氧化物活性的分子模型,但对这些系统的研究仅限于处于高氧化态的金属。在这里,我们合成并表征了铀桥联的U III / U IV和U III / U III配合物的分子和电子结构。这些配合物的反应性研究表明,添加N-杂环后,U-O键很容易断裂,从而分别形成形式上等同的U III和U II,以及铀(IV)末端-氧代副产物。特别是U III / U III氧化物配合物影响吡啶的还原偶联和4,4'-联吡啶的双电子还原,提供了由N杂环氧化还原活性配体桥接的二价铀(III)配合物的独特实例。这些结果提供了对低氧化态金属氧化物化学的深入了解,并证明了使用羰基桥联的U III / U III配合物作为探索U II反应性的策略。
The role of bridging ligands in dinitrogen reduction and functionalization by uranium multimetallic complexes
functionalizing dinitrogen. Here we show that an analogous complex assembled with an oxo instead of a nitride linker also effects the four-electron reduction of dinitrogen, but the reactivity of the resulting oxo–(N2) complex differs significantly from that of the nitride–(N2). Computational studies show a different bonding scheme for the dinitrogen where the bridging nitride does participate in the binding and
Neutral Aminyl Radicals Derived from Azoimidazolium Dyes
作者:Léonard Y. M. Eymann、Alexander G. Tskhovrebov、Andrzej Sienkiewicz、José L. Bila、Ivica Živković、Henrik M. Rønnow、Matthew D. Wodrich、Laurent Vannay、Clémence Corminboeuf、Philip Pattison、Euro Solari、Rosario Scopelliti、Kay Severin
DOI:10.1021/jacs.6b09124
日期:2016.11.23
were obtained by reduction of azoimidazolium dyes with potassium. Structural, spectroscopic, and computational data suggest that the spin density is centered on one of the nitrogen atoms of the former azo group. The reduction of a dimeric dye with an octamethylbiphenylene bridge between the azo groups resulted in the formation of a biradical with largely independent unpaired electrons. Both the monoradicals
N–N bond cleavage in a nitrous oxide–NHC adduct promoted by a PNP pincer cobalt(I) complex
作者:Clément Camp、Lara C.E. Naested、Kay Severin、John Arnold
DOI:10.1016/j.poly.2015.09.001
日期:2016.1
The reactivity of a PNP cobalt(I) complex towards the nitrous oxide N-heterocyclic carbene adduct (NHC–N2O) was explored. Several products were isolated including the cobalt nitrosyl complex (HPNP)Co(NO) (1) and the NHC-derived imine NHCNH (2). This study provides a rare example of metal-mediated rupture of the N–Nbond in a nitrous oxide derivative, a route that could be used to generate late-metal