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91.
92.
Redox‐Active Tetraruthenium Macrocycles Built from 1,4‐Divinylphenylene‐Bridged Diruthenium Complexes 下载免费PDF全文
Stefan Scheerer Dr. Michael Linseis Dr. Evelyn Wuttke Sabrina Weickert Prof. Dr. Malte Drescher Dr. Oliver Tröppner Prof. Dr. Ivana Ivanović‐Burmazović Andreas Irmler Prof. Dr. Fabian Pauly Prof. Dr. Rainer F. Winter 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(28):9574-9590
Metallamacrocylic tetraruthenium complexes were generated by treatment of 1,4‐divinylphenylene‐bridged diruthenium complexes with functionalized 1,3‐benzene dicarboxylic acids and characterized by HR ESI‐MS and multinuclear NMR spectroscopy. Every divinylphenylene diruthenium subunit is oxidized in two consecutive one‐electron steps with half‐wave potential splittings in the range of 250 to 330 mV. Additional, smaller redox‐splittings between the +/2+ and 0/+ and the 3+/4+ and 2+/3+ redox processes, corresponding to the first and the second oxidations of every divinylphenylene diruthenium entity, are due to electrostatic effects. The lack of electronic coupling through bond or through space is explained by the nodal properties of the relevant molecular orbitals and the lateral side‐by‐side arrangement of the divinylphenylene linkers. The polyelectrochromic behavior of the divinylphenylene diruthenium precursors is retained and even amplified in these metallamacrocyclic structures. EPR studies down to T=4 K indicate that the dications 1‐H2+ and 1‐OBu2+ are paramagnetic. The dications and the tetracation of macrocycle 3‐H display intense (dications) or weak ( 3‐H4+ ) EPR signals. Quantum chemical calculations indicate that the four most stable conformers of the macrocycles are largely devoid of strain. Bond parameters, energies as well as charge and spin density distributions of model macrocycle 5‐HMe were calculated for the different charge and spin states. 相似文献
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Matthias Eul Manfred H. Möller Rolf‐Dieter Hoffmann Wolfgang Jeitschko Prof. Dr. Rainer Pöttgen 《无机化学与普通化学杂志》2012,638(2):331-335
The phosphide oxide La2AuP2O was synthesized from lanthanum filings, dried La2O3, gold pieces, and ground red phosphorus in the ideal 1.33:0.33:1:2 ratio in an evacuated silica tube at 1473 K. Small single crystals were obtained by recrystallization in a NaCl/KCl flux. The structure was determined on the basis of single‐crystal X‐ray diffractometer data: new type, C2/m, a = 1537.3(3), b = 427.39(8), c = 1009.2(2) pm, β = 131.02(1) °, wR2 = 0.046, 1102 F2 values, 38 variables. La2AuP2O contains two striking structural motifs: The oxygen atoms are located in La4 tetrahedra. The latter are cis‐edge‐shared forming polymeric cationic [La2O]4+ chains. These cationic units are separated and charge‐balanced by [AuP2]4– polyanions which have monovalent gold in distorted trigonal planar phosphorus coordination. Two crystallographically independent phosphorus sites occur in the polyanion, i.e. isolated P3– besides dumb‐bells P24– (P2–P2 223 pm). La2AuP2O, which crystallizes in the form of ruby red transparent crystals, is an electron precise phosphide oxide (4La3+)(2Au+)(2P3–)(P24–)(2O2–). 相似文献
95.
Rainer Streubel Emanuel Ionescu Nils Hoffmann 《Phosphorus, sulfur, and silicon and the related elements》2013,188(4-5):809-811
Metal-assisted heterocyclic ligand syntheses are reported using 2-H-azaphosphirene complex 1 or 7-phosphanorbornadiene complex 7 as starting material. Thermal decomposition of complex 1 led to 1,2dihydro-1,2,3-azadiphosphete complex 2, which was transformed into 2,6-dihydro-1,3,2,6-diazadiphosphinines 5a, b via ring expansion with carbonitriles 3a, b. Insertion of tert-butyl isonitrile into the P─ P bond of 2 at ambient temperature furnished the first Δ 1 -1,3,5-azadi-phospholene complex 6─P bond of 2 using 7 failed. The 1,2,3,4-azatriphospholene complexes 9a, b were obtained by thermolysis of complex 2 in the presence of functionalized carbonitriles 8a, b. 相似文献
96.
Rainer Bartsch Christian Müller Axel Fischer Peter G. Jones 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4)
Abstract Syntheses and structures of penta- and hexaphosphorus analogues of ferrocene have been described recently1. Unlike their simple ferrocene analogues, these complexes have further ligating potential towards other transition metal centres by virtue of the availability of the ring phosphorus lone-pair electrons that are not involved in the η5-coordination. We now describe the first examples of coordination compounds of the triphospha-ferrocene [Fe(η5-C5Me5) (η5-C2 tBu2P3]. In the ruthenium complex [Fe(η5-C5Me5)(η5-C2 tBu2P3) Ru3(CO)9] 2 two adjacent phosphorus atoms of the η5-C2 tBu2P3 ring are interlinked by a ruthenium carbonyl cluster in which all three ruthenium atoms interact with the phosphorus atoms. The tetrametallic nickel complex [Fe(η5-C5Me5)(η5-C2 tBu2P3)Ni(CO)2]2 3 represents the first example of intermolecular interlinkage of two phospha-ferrocene systems by two metal centres. 相似文献
97.
Ulrich Wannagat Rainer Münstedt 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2-4):233-237
Abstract Dialkylbenzylphosphine imides C6H5CH2–PRR′[dbnd]N″ (R, R′ = CH3, C2H5; R″ = H, CH3, Si(CH3)3 react with aliphatic and aromatic aldehydes in benzene solution on heating to 80°C directly and in high yields according to a Horner-Wittig-reaction with formation of an olefine whereas ketones like benzophenone and acetophenone only perform an O/NR″ exchange (R″ = H). Dialkylbenzylphosphinimide C6H5CH2–PRR′[dbnd]N″ mit R, R′ = CH3, C2H5 und R″ = H, CH3, Si(CH3)3 reagieren mit aliphatischen und aromatischen Aldehyden in benzolischer Lösung beim Erwärmen auf 80°C direkt und mit hohen Ausbeuten im Sinne einer Horner-Wittig-Reaktion unter Olefinbildung, während sich mit Ketonen wie Benzophenon oder Acetophenon nur ein O/NR″-Austausch (R″ = H) vollzieht. 相似文献
98.
99.
Hossein Reza Darabi Abbas Darestani Farahani Mohammad Hashemi Karouei Kioumars Aghapoor Rohoullah Firouzi Rainer Herges 《Supramolecular chemistry》2013,25(9):653-657
A new E,E-stilbenophane was synthesised and characterised. The crystal structure of this cyclophane shows that this molecule has a cup-shaped structure, which hosts a phenyl ring of neighbouring molecule as guest in its cavity with a π–π distance of about 3.7 Å. Moreover, the NMR spectra and theoretical analysis (gauge-independent atomic orbitals (GIAO) and quantum theory of atoms in molecules (QTAIM)) suggest that the silver recognition by E,E-stilbenophane host molecules is based on cation–π interactions in which the π-electrons of the double bonds play a major role. 相似文献
100.