- Oxidative Dephosphorylation of Benzylic Phosphonates with Dioxygen Generating Symmetrical trans-Stilbenes
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Under a dioxygen atmosphere, benzylphosphonates and related phosphoryl compounds can readily produce the corresponding trans-stilbenes in high yields with high selectivity upon treatment with bases. Various functional groups were tolerable under the reaction conditions.
- Huang, Tianzeng,Chen, Tieqiao,Han, Li-Biao
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p. 2959 - 2965
(2018/03/09)
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- PHENACENE COMPOUND, METHOD FOR PRODUCING PHENACENE COMPOUND AND ORGANIC LIGHT EMITTING ELEMENT
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PROBLEM TO BE SOLVED: To provide a phenacene compound having a high fluorescence yield. SOLUTION: The present invention provides a phenacene compound represented by formula (1), where A is a group represented by formula (2); Z1 and Z2/sup
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- Ruthenium stilbenyl and diruthenium distyrylethene complexes: Aspects of electron delocalization and electrocatalyzed isomerization of the Z-isomer
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Regio- and stereoselective insertion of the terminal ethynyl functions of 4-ethynylstilbene, the E and Z isomers of 4,4′-bis(ethynylphenyl)ethene and a backbone-rigidified cyclohexenyl derivative of the Z isomer into the Ru-H bond of the complex RuClH(CO)(PiPr3)2 provides the corresponding vinyl ruthenium complexes, which have been characterized spectroscopically and by X-ray crystallography. Large red shifts of the UV/vis absorption bands evidence efficient incorporation of the vinyl metal subunit(s) into the conjugated π-system. All complexes oxidize at low potentials. The various oxidized forms of all complexes were generated and characterized by UV/vis/NIR, IR and EPR spectroscopies. These studies indicated electrocatalytic Z→E isomerization of the oxidized Z-distyrylethene complex Ru-Z2, which is prevented in its backbone-rigidified derivative Ru-Z2fix. The radical cations of the E and the configurationally stable cyclohexene-bridged Z-derivatives are spin-delocalized on the EPR time scale but charge-localized on the faster IR time scale. The degree of ground-state charge delocalization in the mixed-valent state has been quantified by the incremental shifts of the Ru-CO bands upon stepwise oxidation to the radical cations and the dications and was found to be remarkably large (19% and 9%) considering redox splittings ΔE 1/2 of just 49 or 74 mV. Quantum chemical studies with various levels of sophistication reproduce our experimental results including the electronic spectra of the neutral complexes and the intrinsically localized nature of the radical cations of the dinuclear complexes.
- Linseis, Michael,Zalis, Stanislav,Zabel, Manfred,Winter, Rainer F.
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supporting information
p. 16671 - 16692
(2013/01/15)
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- Transformable periodic mesoporous organosilica materials
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The synthesis of novel periodic mesoporous organosilica (PMO) materials incorporating a mixture of functional monomers (cis- and trans-stilbene-based) and structural monomers has been accomplished. EDX analysis of these materials in combination with HAADF
- Dickson, Steven E.,Crudden, Cathleen M.
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supporting information; experimental part
p. 2100 - 2102
(2010/08/22)
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- Synthesis of nanostructures based on 1,4- and 1,3,5-phenylethynyl units with π-extended conjugation. Carbon networks dendrimer base units
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A convenient and efficient synthesis of 3,5-di(silylethynyl)phenylacetylene and p-[3,5-di(silylethynyl)phenylethynyl]phenylacetylene has been carried out. These compounds serve to prepare nanometer-sized conjugated 1,4- and 1,3,5-phenylethynyl oligomers,
- Rodríguez, J. Gonzalo,Esquivias
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p. 4831 - 4834
(2007/10/03)
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- Synthesis of nanostructures based on 1,4- and 1,3,5-ethynylphenyl subunits with π-extended conjugation. Carbon dendron units
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Nanometer-sized conjugated 1,4- and 1,3,5-ethynylphenyl oligomers were synthesized starting from 3,5-di(trimethylsilylethynyl)phenylacetylene and p-[3,5-di(trimethylsilylethynyl)-1-ethynylphenyl]-phenyl acetylene by cross-coupling reaction with a convenient haloaryl derivative, catalyzed by palladium(II)/copper(I), in excellent yield. The terminal acetylenes were efficiently prepared by a specific protection-deprotection methodology. All ethynylphenyl homologues obtained show fluorescence emission, with the bathochromic shift of approximately 20 nm by each ethynylphenyl unit increasing the conjugate chain. Parallel conjugated ethynylphenyl chains were prepared through the insertion of a 1,5-naphthalene subunit, and the compounds exhibit fluorescence radiation emission.
- Gonzalo Rodriguez,Esquivias, Jorge,Lafuente, Antonio,Diaz, Cristina
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p. 8120 - 8128
(2007/10/03)
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- Synthesis of trans-4,4′-diiodostilbene and other symmetrical trans-stilbenes by Heck reaction of arenediazonium salts with vinyltriethoxysilane
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With anilines as the starting materials, a facile new synthesis of symmetrical trans-stilbenes, in particular of trans-4,4′-diiodostilbene, by (double) Heck reaction of arenediazonium salts with vinyltriethoxysilane is described.
- Sengupta, Saumitra,Bhattacharyya, Sanchita,Sadhukhan, Subir Kumar
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p. 275 - 277
(2007/10/03)
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