Rhodium-Catalyzed [2 + 2 + 2] Cycloaddition of Alkenyl Isocyanates and Alkynes
作者:Robert T. Yu、Tomislav Rovis
DOI:10.1021/ja057803c
日期:2006.3.1
rhodium(I)-catalyzed [2 + 2 + 2] cycloaddition between alkenyl isocyanates and alkynes has been developed. Heating a mixture of an alkenyl isocyanate and a symmetrical internal alkyne in the presence of [Rh(ethylene)2Cl]2/P(4-OMe-C6H4)3 in toluene delivers substituted indolizinones and quinolizinones. Depending on the substrates, a rare fragmentation of the isocyanate unit can be involved within the cycloaddition process
Ruthenium-Catalyzed <i>trans</i>-Hydroalkynylation and <i>trans</i>-Chloroalkynylation of Internal Alkynes
作者:Nagaraju Barsu、Markus Leutzsch、Alois Fürstner
DOI:10.1021/jacs.0c08582
日期:2020.11.4
[Cp*RuCl]4 catalyzes the addition of iPr3SiC≡CX (X = H, Cl) across internal alkynes with formation of 1,3-enyne or 1-chloro-1,3-enyne derivatives, respectively; the reaction follows an unorthodox trans-addition mode. The well-balanced affinities of the different reaction partners to the ruthenium catalyst ensure that crossed addition prevails over homodimerization of the individual components, as can
Water-Soluble Cationic Conjugated Polymers: Response to Electron-Rich Bioanalytes
作者:Sébastien Rochat、Timothy M. Swager
DOI:10.1021/ja4095395
日期:2013.11.27
We report the concise synthesis of a symmetrical monomer that provides a head-to-head pyridine building block for the preparation of cationic conjugated polymers. The obtained poly(pyridinium-phenylene) polymers display appealing properties such as high electron affinity, charge-transport upon n-doping, and optical response to electron-donating analytes. A simple assay for the optical detection of low micromolar amounts of a variety of analytes in aqueous solution was developed. In particular, caffeine could be measured at a 25 mu M detection limit. The reported polymers are also suitable for layer-by-layer film formation.
DIEFENBACH, STEVEN P.
作者:DIEFENBACH, STEVEN P.
DOI:——
日期:——
Increasing the Structural Span of Alkyne Metathesis
作者:Peter Persich、Josep Llaveria、Rudy Lhermet、Teresa de Haro、Robert Stade、Azusa Kondoh、Alois Fürstner
DOI:10.1002/chem.201302320
日期:2013.9.23
new generation of alkyne metathesis catalysts, which are distinguished by high activity and an exquisite functional group tolerance, allows the scope of this transformation to be extended beyond its traditional range. They accept substrates that were previously found problematic or unreactive, such as propargyl alcohol derivatives, electron‐deficient and electron‐rich acetylenes of various types, and