Consecutive palladium-catalyzed Hiyama–Heck reactions in aqueous media under ligand-free conditions
作者:Álvaro Gordillo、Ernesto de Jesús、Carmen López-Mardomingo
DOI:10.1039/b707583a
日期:——
Symmetric and asymmetric (E)-1,2-diarylethenes are synthesized from aryl bromides by consecutive one-pot HiyamaâHeck reactions carried out in water and under air; the only additives required are sodium hydroxide, palladium acetate and poly(ethylene glycol), and the products are isolable in many cases by simple filtration of the water solution.
Synthesis, structure and photophysical properties of a 2D network with gold dicyanide donors coordinated to aza[5]helicene viologen acceptors
作者:Ealin N. Patel、Robert B. Arthur、Aaron D. Nicholas、Eric W. Reinheimer、Mohammad A. Omary、Matthew Brichacek、Howard H. Patterson
DOI:10.1039/c9dt01823a
日期:——
synthesized photoluminescent organic acceptor, 5,10-dimethyl-5,10-diaza[5]helicene is shown to react with dicyanoaurate anions to form a 2D network N,N-dimethylaza[5]helicene dicyanoaurate. The structure of the synthesized complex was investigated via X-ray crystallography showing the presence of [Au(CN)2]− dimers and monomers within the helicene framework. Photophysical measurements between 298 K and 10 K indicate
Synthesis, Structure, and Photochemical Behavior of [5]Heli-viologen Isomers
作者:Xiaoping Zhang、Edward L. Clennan、Navamoney Arulsamy、Rachael Weber、Jacob Weber
DOI:10.1021/acs.joc.6b00835
日期:2016.7.1
primarily determined by the identity of the helical scaffold and is insensitive to the placement of the viologen functional group. The isomers are similar in their photophysical behavior but very different in their photochemicalbehavior.
Synthesis of Erythromycin Derivatives via the Olefin Cross-Metathesis Reaction
作者:Margaret C. Hsu、Adam J. Junia、Anthony R. Haight、Weijiang Zhang
DOI:10.1021/jo049737n
日期:2004.5.1
Olefin cross metathesis (CM) was applied to the synthesis of 6-O-substituted erythromycin derivatives. The reactions were catalyzed by transition metal alkylidene complexes, particularly bis(tricyclohexylphosphine)benzylidine ruthenium (IV) dichloride (Grubbs' first-generation catalyst). This approach allowed for the elaboration of the 6-O-allyl group of highly functionalized macrolides at various
将烯烃交叉复分解(CM)用于6- O-取代的红霉素衍生物的合成。该反应由过渡金属亚烷基络合物,特别是双(三环己基膦)亚苄基钌(IV)二氯化物(Grubbs的第一代催化剂)催化。该方法允许在合成序列的各个阶段精细修饰高度官能化的大环内酯的6- O-烯丙基基团,从而提供具有优异的E-选择性的6 - O -3-芳基-丙烯基产物。在粗混合物中几乎没有或没有发现反应组分的自二聚。初步动力学数据说明了基于底物反应性和空间因素观察到的交叉选择性。
Synthesis, computational, and photophysical characterization of diaza-embedded [4]helicenes and pseudo[4]helicenes and their pyridinium and viologen homologues
作者:Xiaoping Zhang、Edward L. Clennan、Toby Petek、Jacob Weber
DOI:10.1016/j.tet.2016.12.032
日期:2017.2
of three [4]heli-viologens and their helical precursors, and two “pseudo-[4]helicenes” and their alkylated derivatives, which have potential device and catalysis applications, are reported. Their structures and racemization barriers have been explored with the B3LYP/6-311+G(2d,p), M06-2X/6-311+G(2d,p), and M11/6-311+G(2d,p) computational models. The photophysical properties of the helicenes and pseudo-helicenes