Rhodium-Catalyzed Asymmetric Cyclization/Addition Reactions of 1,6-Enynes and Oxa/Azabenzonorbornadienes
作者:Yongyun Zhou、Lu Yu、Jingchao Chen、Jianbin Xu、Zhenxiu He、Guoli Shen、Baomin Fan
DOI:10.1021/acs.orglett.7b04044
日期:2018.3.2
A mild, efficient, and novel rhodium catalyzed asymmetric cyclization–addition domino reaction of oxa/azabenzonorbornadienes and 1,6-enynes is documented. Through the use of a [Rh(COD)2]BF4-(R)-An-SDP catalytic system, highly enantioenriched cyclization–addition products were obtained in good yields and with excellent enantioselectivities.
Merging Gold Catalysis and Brønsted Acid Catalysis for the Synthesis of Tetrahydrobenzo[<i>b</i>][1,8]naphthyridines
作者:Ruxia Yi、Xincheng Li、Boshun Wan
DOI:10.1002/adsc.201701323
日期:2018.3.1
A gold(I)/Brønsted acid‐catalyzed cyclization of 2‐azidobenzaldehydes with 3‐aza‐1,6‐enynes has been developed for the synthesis of tetrahydrobenzo[b][1,8]naphthyridine derivatives. This protocol enabled the modular synthesis of tetracyclic heterocycles in one operation with water and nitrogen gas as the byproducts.
已经开发了金(I)/布朗斯台德酸催化的3-叠氮基-1,6-炔烃对2-叠氮基苯甲醛的环化反应,以合成四氢苯并[ b ] [1,8]萘啶衍生物。该方案能够在一次操作中以水和氮气为副产物,以模块化方式合成四环杂环。
Chiral Spirosiladiphosphines: Ligand Development and Applications in Rh-Catalyzed Asymmetric Hydrosilylation/Cyclization of 1,6-Enynes with Enhanced Reactivity
conformations by the direct displacement of the spiro atom remains elusive. Herein, we report the application of Si-centered spirodiphosphine (Si-SDP) ligands in the enantioselective hydrosilylation/cyclization of 1,6-enynes. The Si-SDPs showed superior reactivity to existing C2-symmetric diphosphines, allowing the generation of a range of chiral pyrrolidines with high yields and enantioselectivity (up to 96%
important and efficient strategies for the synthesis of valuable heterocycles with structural diversity and complexity. Organic electrochemistry has emerged as an effective tool for the sustainable molecular synthesis. Herein, we describe an electrooxidative radical cascade cyclization of 1,6-enynes to access two new classes of sulfonamides, containing medium-sized rings. Differences in the activation barrier