A liquid-crystalline perylene tetracarboxylic bisimide derivative bearing trisiloxan-2-yl moieties: influence on mesomorphic properties and electron transport
Mesomorphic and electron transport properties are compared for liquid-crystalline perylene tetracarboxylic bisimide derivatives bearing linear disiloxane and trisiloxane chains, as well as trisiloxan-2-yl groups.
Double Ring-Closing Metathesis Reaction of Nitrogen-Containing Tetraenes: Efficient Construction of Bicyclic Alkaloid Skeletons and Synthetic Application to Four Stereoisomers of Lupinine and Their Derivatives
作者:Shengming Ma、Bukuo Ni
DOI:10.1002/chem.200305581
日期:2004.7.5
The doublering-closingmetathesisreaction of nitrogen-containingtetraenes was studied. The selectivity of the fused/dumbbell-type products can be controlled by the electronic/steric effects of the substituents attached to the C[double bond]C bonds and the s-cis/s-trans conformational ratios of the substrates. This methodology has also been successfully applied to the enantioselective synthesis of
Highly efficient, base-catalysed, intramolecular hydroamination of non-activated olefins
作者:Coralie Quinet、Pierre Jourdain、Christophe Hermans、Ali Ates、Isabelle Lucas、István E. Markó
DOI:10.1016/j.tet.2007.11.066
日期:2008.2
The intramolecularhydroamination of a large variety of non-activated alkenes can be efficiently catalysed by small amounts of lithium bases, providing smoothly and in high yields the corresponding five- and six-membered ring heterocycles. Fused and bridged bicyclic amines, of varying ring sizes, can be readily prepared either by a sequential hydroamination process or by a tandem, double addition reaction
Stereoselective Copper-Catalyzed Intramolecular Alkene Aminooxygenation: Effects of Substrate and Ligand Structure on Selectivity
作者:Monissa C. Paderes、Sherry R. Chemler
DOI:10.1002/ejoc.201100444
日期:2011.7
A new protocol for diastereoselective copper-catalyzed intra-molecular alkene aminooxygenation, which provides methyleneoxy-functionalized disubstituted pyrrolidines and five-membered cyclic ureas from the corresponding γ-alkenyl sulfonamides and N-allylureas, is reported. In addition, some success was achieved in enantioselective desymmetrizations reactions. We discovered that the level of enantioselectivity
报道了一种非对映选择性铜催化分子内烯烃氨基氧化的新方案,该方案从相应的 γ-烯基磺酰胺和 N-烯丙基脲中提供亚甲氧基官能化的二取代吡咯烷和五元环脲。此外,对映选择性去对称化反应也取得了一些成功。我们发现对映选择性和非对映选择性的水平可以通过选择铜 (II) 配体和底物 N 取代基来调节。
On the stereoselective bicyclization of aminodienes catalyzed by chelating diamide complexes of the group 3 metals. A direct comparison of Sc(iii) and Y(iii) bis(amide)s with an application to the synthesis of alkaloid 195F
作者:Tao Jiang、Tom Livinghouse、Helena M. Lovick
DOI:10.1039/c1cc15399d
日期:——
Highly diastereoselective bicyclizations of aminodienes catalyzed by chelating diamide complexes of Sc(III) and Y(III) that lead to pyrrolizidines and indolizidines are described. This bis(annulation) procedure has been utilized in a concise synthesis of the pyrrolizidine alkaloid 195F.