769-35-7Relevant academic research and scientific papers
Mechanistic Insight into H/D Exchange by a Pentanuclear Ni-H Cluster and Synthesis and Characterization of Structural Analogues of Potential Intermediates
Shoshani, Manar M.,Liu, Junyang,Johnson, Samuel A.
, p. 116 - 126 (2018)
Experiments to gain mechanistic insight into catalytic H/D exchange of unactivated arenes by [(iPr3P)Ni]5H6 (1) are described. The reaction order with respect to 1, arene substrate, and added iPr3P were determined, as well as the temperature dependence of reaction rate. Site-selectivity data were obtained by monitoring the reaction of 1 with fluorobenzene and 2-methoxynaphthalene. H/D exchange competition reactions between arenes reacted with 1 were performed. The addition of an excess of Hg to a solution of 1 provided the new heterometallic cluster [(iPr3P)Ni]5H6(μ4-Hg) (2); this species also undergoes H/D exchange with C6D6, albeit more slowly than 1. Reaction of cluster 1 with TlCp (Cp = C5H5) gave (η5-Cp)Ni[(iPr3P)Ni]4(μ2-H)4(μ4-Tl) (3) with the loss of H2. A similar transfer of cyclopentadienyl to Ni occurred when 1 was reacted with MgCp2, to give (η5-Cp)Ni[(iPr3P)Ni]4H6(μ4-MgCp) (4), but not H2 loss. Reaction of 1 with cyclopentadiene gave the 5-coordinate hydride complex (η5-Cp)Ni[(iPr3P)Ni]4(μ2-H)4(μ5-H) (5). The Cp? analogue, (η5-Cp)Ni[(iPr3P)Ni]4(μ2-H)4(μ5-H) (6) (where Cp? = C5Me5), was synthesized by reacting 1 with LiCp? in THF, or by reaction of 1 with pentamethylcyclopentadiene.
Facile H/D exchange at (hetero)aromatic hydrocarbons catalyzed by a stable trans-dihydride n-heterocyclic carbene (NHC) iron complex
De Ruiter, Graham,Garhwal, Subhash,Kaushansky, Alexander,Fridman, Natalia,Shimon, Linda J.W.
supporting information, p. 17131 - 17139 (2020/11/09)
Earth-abundant metal pincer complexes have played an important role in homogeneous catalysis during the last ten years. Yet, despite intense research efforts, the synthesis of iron PCcarbeneP pincer complexes has so far remained elusive. Here we report the synthesis of the first PCNHCP functionalized iron complex [(PCNHCP)FeCl2] (1) and the reactivity of the corresponding trans-dihydride iron(II) dinitrogen complex [(PCNHCP)- Fe(H)2N2)] (2). Complex 2 is stable under an atmosphere of N2 and is highly active for hydrogen isotope exchange at (hetero)aromatic hydrocarbons under mild conditions (50 °C, N2). With benzene-d6 as the deuterium source, easily reducible functional groups such as esters and amides are well tolerated, contributing to the overall wide substrate scope (e.g., halides, ethers, and amines). DFT studies suggest a complex assisted σ-bond metathesis pathway for C(sp2)-H bond activation, which is further discussed in this study.
