Stability and Dynamic Processes in 16VE Iridium(III) Ethyl Hydride and Rhodium(I) σ-Ethane Complexes: Experimental and Computational Studies
作者:Marc D. Walter、Peter S. White、Cynthia K. Schauer、Maurice Brookhart
DOI:10.1021/ja4079539
日期:2013.10.23
Iridium(I) and rhodium(I) ethyl complexes, (PONOP)M(C2H5) (M = Ir (1-Et), Rh (2-Et)) and the iridium(I) propyl complex (PONOP)Ir(C3H7) (1-Pr), where PONOP is 2,6-(tBu2PO)2C5H3N, have been prepared. Low-temperature protonation of the Ir complexes yields the alkyl hydrides, (PONOP)Ir(H)(R) (1-(H)(Et)(+) and 1-(H)(Pr)(+)), respectively. Dynamic (1)H NMR characterization of 1-(H)(Et)(+) establishes site
铱(I)和铑(I)乙基配合物,(PONOP)M(C2H5)(M = Ir(1-Et),Rh(2-Et))和铱(I)丙基配合物(PONOP)Ir(C3H7 ) (1-Pr),其中 PONOP 是 2,6-(tBu2PO)2C5H3N,已制备。Ir 配合物的低温质子化产生烷基氢化物,(PONOP)Ir(H)(R)(1-(H)(Et)(+) 和 1-(H)(Pr)(+)),分别. 1-(H)(Et)(+) 的动态 (1)H NMR 表征建立了 Ir-H 和 Ir-CH2 质子之间的位点交换(ΔG(exH)(‡)(-110 °C) = 7.2(1) ) kcal/mol),指向 σ-乙烷中间体。通过动态 (13)C NMR 光谱,测量了 α 和 β 碳(“链行走”)之间的交换势垒(ΔG(exC)(‡)(-110 °C) = 8.1(1) kcal/mol) . 乙烷损失的屏障为 17.4(1) kcal/mol