Cooperative Al–H Bond Activation in DIBAL-H: Catalytic Generation of an Alumenium-Ion-Like Lewis Acid for Hydrodefluorinative Friedel–Crafts Alkylation
作者:Francis Forster、Toni T. Metsänen、Elisabeth Irran、Peter Hrobárik、Martin Oestreich
DOI:10.1021/jacs.7b09444
日期:2017.11.15
donor-acceptor σ(Ru-H) → Al interaction. Despite the extra stabilization of the aluminum center by the interaction with both the sulfur atom and the Ru-H bond, the hydroalane adducts are found to be stronger Lewisacids and electrophiles than the free ruthenium catalyst and DIBAL-H in its different aggregation states. Hence, the DIBAL-H molecule and its Al-H bond are activated by the Ru-S bond, but these
C(sp<sup>3</sup>)–F Bond Activation of CF<sub>3</sub>-Substituted Anilines with Catalytically Generated Silicon Cations: Spectroscopic Evidence for a Hydride-Bridged Ru–S Dimer in the Catalytic Cycle
作者:Timo Stahl、Hendrik F. T. Klare、Martin Oestreich
DOI:10.1021/ja311398j
日期:2013.1.30
Heterolytic splitting of the Si-H bond mediated by a Ru-S bond forms a sulfur-stabilized silicon cation that is sufficiently electrophilic to abstract fluoride from CF(3) groups attached to selected anilines. The ability of the Ru-H complex, generated in the cooperative activation step, to intramolecularly transfer its hydride to the intermediate carbenium ion (stabilized in the form of a cationic
Copper(<scp>i</scp>) clusters with bulky dithiocarboxylate, thiolate, and selenolate ligands
作者:Pokpong Rungthanaphatsophon、Charles L. Barnes、Justin R. Walensky
DOI:10.1039/c6dt02709a
日期:——
coordination chemistry of copper has interest due to its use in biological systems as well as for photochemical and medicinal properties. We report the coordination chemistry of copper(I) complexes using terphenyl-based dithiocarboxylate, thiolate, and selenolate ligands. The number of metal ions of the resulting complexes can be tuned by varying the steric properties of the terphenyl ligands, changing
铜的配位化学因其在生物系统以及光化学和医学特性中的使用而引起人们的兴趣。我们报告了使用基于三联苯基的二硫代羧酸盐,硫醇盐和硒酸盐配体的铜(I)配合物的配位化学。可以通过改变三联苯配体的空间性质,改变起始材料以及添加PEt 3来调节所得配合物的金属离子数量。另外,三联苯配体的空间拥挤导致反应性变化。例如,二硫化碳与[Cu(2,6-(Ph)2 C 6 H 3)] 2的反应导致插入到铜碳键中,与[Cu(2,4,6-(Mes)2 C 6 H 3)]不发生反应,Mes = 2,4,6-Me 3 C 6 H 2,或[Et 3 PCu(2,4,6-(Mes)2 C 6 H 2)2 C 6 H 3 ]。描述了使用NMR和IR光谱以及X射线晶体学对新的铜(I)配合物的合成和表征。
Direct Catalytic Access to N-Silylated Enamines from Enolizable Imines and Hydrosilanes by Base-Free Dehydrogenative SiN Coupling
作者:Julia Hermeke、Hendrik F. T. Klare、Martin Oestreich
DOI:10.1002/chem.201402866
日期:2014.7.21
α‐proton rather than α‐deprotonation of the enolizable imine followed by reaction with an electrophilic silicon reagent. The silicon electrophile, stabilized by a sulfur atom, is generated by cooperative activation of an SiH bond at the RuS bond of a tethered ruthenium(II) thiolate complex. After transfer of the silicon cation onto the imine nitrogen atom, the remaining ruthenium(II) hydride fulfills
Catalytic Dehydrogenative Stannylation of C(sp)–H Bonds Involving Cooperative Sn–H Bond Activation of Hydrostannanes
作者:Francis Forster、Victoria M. Rendón López、Martin Oestreich
DOI:10.1021/jacs.7b13088
日期:2018.1.31
a stannylium-ion-like tin electrophile by heterolytic cleavage of the Sn-H bond in hydrostannanes at the Ru-S bond of Ohki-Tatsumi complexes is reported. Reacting these activated hydrostannanes with terminal acetylenes does not lead to hydrostannylation of the C-C triple bond but to dehydrogenative stannylation of the alkyne terminus. The scope of this rare direct C(sp)-H bond stannylation with hydrostannanes