Synthesis of 1-Amino-2<i>H</i>-quinolizin-2-one Scaffolds by Tandem Silver Catalysis
作者:Xiao-Long Min、Chao Sun、Ying He
DOI:10.1021/acs.orglett.8b03935
日期:2019.2.1
An efficient tandem cycloisomerization–amination reaction catalyzed by silver is described. This rapid and atom-economic reaction delivered 1-amino-2H-quinolizin-2-one scaffolds in high yields under mild conditions. The reaction could be extended to an asymmetric version albeit with moderate enantioselective excess of the products. In addition, the products can be easily reduced into various azabicycles
Direct Synthesis of 4-Quinolones via Copper-Catalyzed Anilines and Alkynes
作者:Xuefeng Xu、Xu Zhang
DOI:10.1021/acs.orglett.7b02495
日期:2017.9.15
and direct approach for constructing 4-quinolones from simple and readily available anilines and alkynes is described. Under the optimal conditions, both N-alkyl- and N-aryl-substituted anilines can be successfully transformed into the corresponding 4-quinolones. This reaction is characterized by mild reaction conditions, high functional-group tolerance, and amenability to gram-scale synthesis.
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
Rh-Catalyzed Enantioselective [2 + 2] Cycloaddition of Alkynyl Esters and Norbornene Derivatives
作者:Takanori Shibata、Kyoko Takami、Ai Kawachi
DOI:10.1021/ol060055r
日期:2006.3.1
[reaction: see text] The enantioselective [2 + 2] cycloaddition of alkynes possessing an ester functionality and norbornene derivatives proceeded efficiently using a chiral rhodium catalyst. The chiral tri- and tetracyclic cyclobutenes were obtained in moderate to high ee.
Salt-Free Strategy for the Insertion of CO<sub>2</sub>
into C−H Bonds: Catalytic Hydroxymethylation of Alkynes
作者:Timo Wendling、Eugen Risto、Thilo Krause、Lukas J. Gooßen
DOI:10.1002/chem.201800526
日期:2018.4.20
A copper(I) catalyst enables the insertion of carbondioxide into alkyne C−H bonds by using a suitable organic base with which hydrogenation of the resulting carboxylate salt with regeneration of the base becomes thermodynamically feasible. In the presence of catalytic copper(I) chloride/4,7‐diphenyl‐1,10‐phenanthroline, polymer‐bound triphenylphosphine, and 2,2,6,6‐tetramethylpiperidine as the base
铜(I)催化剂可通过使用合适的有机碱将二氧化碳插入炔烃的C H键中,利用该有机碱在热力学上可实现对羧酸盐的氢化以及碱的再生。在催化氯化铜(I)/ 4,7-二苯基-1,10-菲咯啉,聚合物结合的三苯基膦和2,2,6,6-四甲基哌啶为碱的情况下,末端炔烃在15 bar CO下进行羧化反应2,室温。过滤后,可以在铑/钼催化剂下将炔羧酸铵氢化为伯醇和水,以再生胺碱。这证明了无盐整体工艺的可行性,在该工艺中,二氧化碳可充当CH功能中C1的基石。