CuII-catalyzed regioselective borylation of alkynes and alkenes
作者:Shiwen Liu、Xiaojun Zeng、Bo Xu
DOI:10.1016/j.tetlet.2016.06.077
日期:2016.8
We developed a regioselective borylation of alkynes and alkenes protocol based on air-stable CuII/multi-dentate ligand system. Our catalytic system gives exclusive β-borylation products for most substrates in excellent chemical yields. We propose that multi-dentate electron poor nitrogen ligands can effectively discourage the formation of α-addition product through the steric hindrance and at same
我们开发了基于空气稳定的Cu II /多齿配体系统的炔烃和烯烃方案的区域选择性硼化。我们的催化系统以优异的化学收率为大多数底物提供独家的β-硼化产物。我们提出,多齿电子贫氮配体可以通过空间位阻有效地阻止α-加成产物的形成,同时保持良好的反应性。
Binding a meridional ligand in a facial geometry: A square peg in a round hole
作者:Briana R. Schrage、Dominick Vitale、Kimberly A. Kelly、Victor N. Nemykin、Richard S. Herrick、Christopher J. Ziegler
DOI:10.1016/j.jorganchem.2020.121331
日期:2020.7
bis(pyridylimino)isoindoline (BPI) ligand is a tridentate chelate that binds to metals via a meridional coordination mode. However, when this ligand forms a complex with Re(CO)3, an almost exclusively facial moiety, the BPI ligand deforms to coordinate in a facial mode. We have investigated this deformation via structural and theoretical means, and the non-planar binding mode of the ligand bathochromically shifts
Copper-Catalyzed Oxidative Dehydrogenative Carboxylation of Unactivated Alkanes to Allylic Esters via Alkenes
作者:Ba L. Tran、Matthias Driess、John F. Hartwig
DOI:10.1021/ja510093x
日期:2014.12.10
with various substituted benzoic acids to produce the corresponding allylic esters. Spectroscopic studies (EPR, UV–vis) revealed that the resting state of the catalyst is [(BPI)Cu(O2CPh)] (1-O2CPh), formed from [(BPI)Cu(PPh3)2], oxidant, and benzoic acid. Catalytic and stoichiometric reactions of 1-O2CPh with alkyl radicals and radical probes imply that C–H bondcleavage occurs by a tert-butoxy radical
Mechanism of <i>N</i>,<i>N</i>,<i>N</i>-Amide Ruthenium(II) Hydride Mediated Acceptorless Alcohol Dehydrogenation: Inner-Sphere β-H Elimination versus Outer-Sphere Bifunctional Metal–Ligand Cooperativity
作者:Kuei-Nin T. Tseng、Jeff W. Kampf、Nathaniel K. Szymczak
DOI:10.1021/acscatal.5b00952
日期:2015.9.4
transformations between ketones and alcohols via sequential hydrogenation–dehydrogenation reactions are efficiently achieved using a single precatalyst HRu(bMepi)(PPh3)2 (bMepi = 1,3-bis(6′-methyl-2′-pyridylimino)isoindolate). The catalytic mechanism of HRu(bMepi)(PPh3)2 mediated acceptorless alcoholdehydrogenation (AAD) has been investigated by a series of kinetic and isotopic labeling studies, isolation
Mechanism-Based Development of a Low-Potential, Soluble, and Cyclable Multielectron Anolyte for Nonaqueous Redox Flow Batteries
作者:Christo S. Sevov、Sydney L. Fisher、Levi T. Thompson、Melanie S. Sanford
DOI:10.1021/jacs.6b07638
日期:2016.11.30
that occur during electrochemical cycling. Ultimately, these studies led to the identification of nickel BPI complexes that could undergo stable charge-discharge cycling (<5% capacity loss over 200 cycles) as well as a derivative that possesses the previously unprecedented combination of high solubility (>700 mM in CH3CN), multiple electron transfers at low redox potentials (-1.7 and -1.9 V versus Ag/Ag+)