PyridineN‐oxide–BF2CF3 and –BF2C2F5 complexes and their derivatives were synthesized. Most of the complexes show fluorescence both in solution and in the solid state. By expanding the π‐conjugated skeleton, the color of the fluorescence could be changed dramatically. A fluorophore with a high solvent dependency could also be produced. Since such compounds can be synthesized on a gram scale in high
Two-photon spectroscopy of cyclometalated iridium complexes
作者:Robert M. Edkins、Sylvia L. Bettington、Andrés E. Goeta、Andrew Beeby
DOI:10.1039/c1dt11164g
日期:——
The near-infrared two-photon absorption (TPA) spectra of a series of cyclometalated iridium complexes have been measured. These complexes exhibit moderately large TPA cross-sections of approximately 20 GM at the biological relevant wavelength of 800 nm. A new complex has been designed and synthesised, and found to have an increased cross-section of 44 GM at 800 nm. Full photophysical characterisation of this complex is presented.
A highly selective hydrogenation of alkynesusing an air-stable and readily available manganese catalyst has been achieved. The reaction proceeds under mild reaction conditions and tolerates various functional groups, resulting in (Z)-alkenes and allylic alcohols in high yields. Mechanistic experiments suggest that the reaction proceeds via a bifunctional activation involving metal–ligand cooperativity
Cyanophosphates (CPs) can be easily prepared from either ketones or aldehydes, and their reaction with NaN3–Et3N·HCl results in the formation of azidotetrazoles. Under microwave irradiation, successive fragmentation of the azidotetrazoles generates alkylidene carbenes that undergo [1,2]-rearrangement and are transformed into homologous alkynes. Treatment of ketone-derived CPs with TMSN3 and Bu2SnO
Full Cleavage of C≡C Bond in Electron-Deficient Alkynes via Reaction with Ethylenediamine
作者:Sergei F. Vasilevsky、Maria P. Davydova、Victor I. Mamatyuk、Nikolay Tsvetkov、Audrey Hughes、Denis S. Baranov、Igor V. Alabugin
DOI:10.1071/ch17026
日期:——
Reaction of 1,2-diaminioethane (ethylenediamine) with electron-deficient alkynes leads to full scission of the C≡Cbond even in the absence of a keto group directly attached to the alkyne. This process involves oxidation of one of the alkyne carbons into C2 of a 2-R-4,5-dihydroimidazole with the concomitant reduction of the other carbon to a methyl group. The sequence of Sonogashira coupling with the
1,2-二氨基乙烷(乙二胺)与缺电子的炔烃反应会导致C≡C键完全断裂,即使没有直接连接到炔烃上的酮基也是如此。该方法涉及将炔烃碳之一氧化成2 - R -4,5-二氢咪唑的C2,同时将另一个碳还原成甲基。这项工作中所述的Sonogashira与乙二胺介导的片段化偶联的序列可用于甲基或4,5-二氢咪唑-2-基部分选择性取代芳基卤化物中的卤素。