Palladium-catalyzed cascade carboesterification of norbornene with alkynes
作者:Wanqing Wu、Can Li、Jianxiao Li、Huanfeng Jiang
DOI:10.1039/c8ob01799a
日期:——
An efficient and convenient palladium-catalyzed cascade carboesterification of norbornenes (NBE) with alkynes has been accomplished to afford functionalized α-methylene γ-lactone and tetrahydrofuran derivatives in good to excellent yields. This new strategy exhibits excellent atom- and step-economy, good functional group tolerance and broad substrate scope. In particular, NBE-palladium species was
A simple and efficient synthesis of cyclopentadienones via palladium-catalyzed cyclocarbonylation of alkynes under atmosphericpressure of carbonmonoxide has been developed. The transformation was carried out under mild and ligand-free conditions, a wide range of substrates and exceptional functional group tolerance.
preparation of trinuclear copper(I) complexes with triscarbene ligands are presented, which yield higher purity products than the one previously described. The first crystal structure of one of these complexes is reported and confirms the expected structure. The trinuclear complexes proved to be efficient catalysts of Ullmann-type reactions as well as of the Sonogashira reaction.
Gold(I) can exhibit a cooperative effect with triphenylphosphine, accelerating the triphenylphosphine-mediated partial hydrogenation of activated alkynes. In this protocol, 3-arylpropiolates are selectively reduced to the Z-isomer when the aryl ring bears an electron-donor substituent, whereas 3-arylpropynones are reduced to the E-isomers.
heterocycles due to their wide range of bioactivities. An efficient silver-catalyzed intermolecular cyclization of 2-aminopyridines with various alkynoates has been developed. 2-Substituted 4H-pyrido[1,2-a]pyrimidin-4-ones containing a wide range of functional groups are synthesized in the standard conditions. This transformation is conducted under convenient conditions and affords products in good yields
嘧啶酮由于其广泛的生物活性而成为重要的含氮杂环之一。已经开发了有效的银催化的2-氨基吡啶与各种链烷酸酯的分子间环化。在标准条件下合成含有2-官能取代的4 H-吡啶并[1,2 - a ]嘧啶-4-酮。该转化是在方便的条件下进行的,并以高收率提供产物。