Escomel Léon, Del Rosal Iker, Maron Laurent, Jeanneau Erwann, Veyre Laurent, Thieuleux Chloé, Camp Clément
Laboratory of Catalysis, Polymerization, Processes and Materials, CP2M UMR 5128, Université de Lyon, Institut de Chimie de Lyon, CNRS, Université Lyon 1, ESCPE Lyon, 43 Bd du 11 Novembre 1918, F-69616 Villeurbanne, France.
Université de Toulouse, CNRS, INSA, UPS, UMR 5215, LPCNO, 135 Avenue de Rangueil, F-31077 Toulouse, France.
J Am Chem Soc. 2021 Mar 31;143(12):4844-4856. doi: 10.1021/jacs.1c01725. Epub 2021 Mar 18.
The iridium tetrahydride complex CpIrH reacts with a range of isobutylaluminum derivatives of general formula Al(Bu)(OAr) ( = 1, 2) to give the unusual iridium aluminum species [CpIrHAl(Bu)(OAr)] () via a reductive elimination route. The Lewis acidity of the Al atom in complex is confirmed by the coordination of pyridine, leading to the adduct [CpIrHAl(Bu)(OAr)(Py)] (). Spectroscopic, crystallographic, and computational data support the description of these heterobimetallic complexes and as featuring strongly polarized Al(III)-Ir(III) interactions. Reactivity studies demonstrate that the binding of a Lewis base to Al does not quench the reactivity of the Ir-Al motif and that both species and promote the cooperative reductive cleavage of a range of heteroallenes. Specifically, complex promotes the decarbonylation of CO and AdNCO, leading to CO (trapped as CpIrH(CO)) and the alkylaluminum oxo ((Bu)(OAr)Al(Py) ()) and ureate ({Al(OAr)(Bu)[κ-(N,O)AdNC(O)NHAd]} ()) species, respectively. The bridged amidinate species Cp*IrH(μ-CyNC(H)NCy)Al(Bu)(OAr) () is formed in the reaction of with dicyclohexylcarbodiimine. Mechanistic investigations via DFT support cooperative heterobimetallic bond activation processes.
四氢化铱配合物CpIrH与一系列通式为Al(Bu)(OAr)（= 1, 2）的异丁基铝衍生物反应，通过还原消除途径生成不寻常的铱铝物种[CpIrHAl(Bu)(OAr)]（）。配合物中Al原子的路易斯酸性通过吡啶的配位得以证实，生成加合物[CpIrHAl(Bu)(OAr)(Py)]（）。光谱、晶体学和计算数据支持将这些异双金属配合物和描述为具有强极化的Al(III)-Ir(III)相互作用。反应性研究表明，路易斯碱与Al的结合不会淬灭Ir-Al基序的反应性，并且物种和都能促进一系列杂联烯的协同还原裂解。具体而言，配合物促进CO和AdNCO的脱羰反应，分别生成CO（捕获为CpIrH(CO)）和烷基铝氧代物((Bu)(OAr)Al(Py)（）)以及脲化物({Al(OAr)(Bu)[κ-(N,O)AdNC(O)NHAd]}（）)物种。桥联脒物种Cp*IrH(μ-CyNC(H)NCy)Al(Bu)(OAr)（）在与二环己基碳二亚胺的反应中形成。通过密度泛函理论进行的机理研究支持协同异双金属键活化过程。
