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101.
The synthesis of M(II)(2) complexes (M(II)=Co, Mn) with terminal hydroxo ligands has been achieved utilizing a dinucleating ligand containing a bridging pyrazolate unit and appended (neopentyl)aminopyridyl groups. Structural studies on the complexes revealed that the M(II)-OH units are positioned in a syn-configuration, placing the hydroxo ligands in close proximity (ca. 3 ? apart), which may be a prerequisite for water oxidation. 相似文献
102.
Dr. David J. Dibble Dr. Young S. Park Amir Mazaheripour Mehran J. Umerani Dr. Joseph W. Ziller Prof. Alon A. Gorodetsky 《Angewandte Chemie (International ed. in English)》2015,54(20):5883-5887
Graphene nanoribbons (GNRs) represent promising materials for the next generation of nanoscale electronics. However, despite substantial progress towards the bottom‐up synthesis of chemically and structurally well‐defined all‐carbon GNRs, strategies for the preparation of their nitrogen‐doped analogs remain at a nascent stage. This scarce literature precedent is surprising given the established use of substitutional doping for tuning the properties of electronic materials. Herein, we report the synthesis of a previously unknown class of polybenzoquinoline‐based materials, which have potential as GNR precursors. Our scalable and facile approach employs few synthetic steps, inexpensive commercial starting materials, and straightforward reaction conditions. Moreover, due to the importance of quinoline derivatives for a variety of applications, the reported findings may hold implications across a diverse range of chemical and physical disciplines. 相似文献
103.
Ludovic Castro Stéphanie Labouille Doug R. Kindra Dr. Joseph W. Ziller Dr. Francois Nief Prof. Dr. William J. Evans Prof. Dr. Laurent Maron 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(25):7886-7895
Reaction mechanisms for the oxidative reactions of CO2 and COS with [(C5Me5)2Sm] have been investigated by means of DFT methods. The experimental formation of oxalate and dithiocarbonate complexes is explained. Their formation involve the samarium(III) bimetallic complexes [(C5Me5)2Sm‐CO2‐Sm(C5Me5)2] and [(C5Me5)2Sm‐COS‐Sm(C5Me5)2] as intermediates, respectively, ruling out radical coupling for the formation of the oxalate complex. 相似文献
104.
105.
A strategy to enable reactivity analogous to oxidative addition is presented for d(0) transition-metal complexes. The reaction of the redox-active ligand 2,4-di-tert-butyl-6-tert-butylamidophenolate (ap) with ZrCl(4)(THF)(2) affords the new complex Zr(IV)(ap)(2)(THF)(2). This compound is formally zirconium(IV) and contains no d electrons; however, exposure of Zr(IV)(ap)(2)(THF)(2) to chlorine gas results in swift chlorine addition at the zirconium metal center via one-electron oxidation of each ap ligand. The diradical product, Zr(IV)Cl(2)(isq)(2) (isq = 2,4-di-tert-butyl-6-tert-butyliminosemiquinone), has been characterized by X-ray crystallography, electron paramagnetic resonance spectroscopy, and SQUID magnetometery. 相似文献
106.
Lorenz V Schmiege BM Hrib CG Ziller JW Edelmann A Blaurock S Evans WJ Edelmann FT 《Journal of the American Chemical Society》2011,133(5):1257-1259
The use of the superbulky cyclooctatetraenide dianion ligand [C(8)H(6)(SiPh(3))(2)](2-) (= COT(BIG)) in organo-f-element chemistry leads to unprecedented effects such as the formation of a significantly bent anionic Ce(III) sandwich complex, a novel cerocene formed by sterically induced SiPh(3) group migration, as well as the first example of a bent uranocene. 相似文献
107.
Fang M Lee DS Ziller JW Doedens RJ Bates JE Furche F Evans WJ 《Journal of the American Chemical Society》2011,133(11):3784-3787
Examination of the Y[N(SiMe(3))(2)](3)/KC(8) reduction system that allowed isolation of the (N(2))(3-) radical has led to the first evidence of Y(2+) in solution. The deep-blue solutions obtained from Y[N(SiMe(3))(2)](3) and KC(8) in THF at -35 °C under argon have EPR spectra containing a doublet at g(iso) = 1.976 with a 110 G hyperfine coupling constant. The solutions react with N(2) to generate (N(2))(2-) and (N(2))(3-) complexes {[(Me(3)Si)(2)N](2)(THF)Y}(2)(μ-η(2):η(2)-N(2)) (1) and {[(Me(3)Si)(2)N](2)(THF)Y}(2)(μ-η(2):η(2)-N(2))[K(THF)(6)] (2), respectively, and demonstrate that the Y[N(SiMe(3))(2)](3)/KC(8) reaction can proceed through an Y(2+) intermediate. The reactivity of (N(2))(3-) radical with proton sources was probed for the first time for comparison with the (N(2))(2-) and (N(2))(4-) chemistry. Complex 2 reacts with [Et(3)NH][BPh(4)] to form {[(Me(3)Si)(2)N](2)(THF)Y}(2)(μ-N(2)H(2)), the first lanthanide (N(2)H(2))(2-) complex derived from dinitrogen, as well as 1 as a byproduct, consistent with radical disproportionation reactivity. 相似文献
108.
109.
Existence and non-existence of homogeneous Einstein metrics 总被引:5,自引:0,他引:5
110.