据报道,氢化钌/布朗斯台德酸催化的串联序列可用于合成1,3,4,9-四氢吡喃[3,4- b ]吲哚(THPIs)和相关的氧环骨架。该过程被设计的前提是容易得到的烯丙基醚将经历连续的异构化,第一至烯醇醚(RU催化),然后到oxocarbenium离子(布朗斯台德酸催化)适合于内 环化栓系亲核体。该方法不仅为合成THPI的传统oxa-Pictet-Spengler反应提供了有吸引力的替代方法,而且还方便地获得THPI同类物和其他重要的乙环(如乙缩醛)。
据报道,氢化钌/布朗斯台德酸催化的串联序列可用于合成1,3,4,9-四氢吡喃[3,4- b ]吲哚(THPIs)和相关的氧环骨架。该过程被设计的前提是容易得到的烯丙基醚将经历连续的异构化,第一至烯醇醚(RU催化),然后到oxocarbenium离子(布朗斯台德酸催化)适合于内 环化栓系亲核体。该方法不仅为合成THPI的传统oxa-Pictet-Spengler反应提供了有吸引力的替代方法,而且还方便地获得THPI同类物和其他重要的乙环(如乙缩醛)。
Tandem Olefin Isomerization/Cyclization Catalyzed by Complex Nickel Hydride and Brønsted Acid
作者:Prasad M. Kathe、Alexandru Caciuleanu、Andreas Berkefeld、Ivana Fleischer
DOI:10.1021/acs.joc.0c02033
日期:2020.12.4
We disclose a nickel/Brønsted acid-catalyzed tandem process consisting of double bond isomerization of allyl ethers and amines and subsequent intramolecular reaction with nucleophiles. The process is accomplished by [(Me3P)4NiH]N(SO2CF3)2 in the presence of triflic acid. The methodology provides rapid access to tetrahydropyran-fused indoles and other oxacyclic scaffolds under very low catalyst loadings
Pd-Catalyzed Tandem Isomerization/Cyclization for the Synthesis of Aromatic Oxazaheterocycles and Pyrido[3,4-<i>b</i>]indoles
作者:Linglong Ding、Yan-Ning Niu、Xiao-Feng Xia
DOI:10.1021/acs.joc.1c00770
日期:2021.8.6
An effient tandem process consisting of palladium-catalyzed double-bond isomerization of long-chain olefins and subsequent intramolecular cyclization promoted by B2(OH)2 for the synthesis of aromatic oxazaheterocycles is disclosed. This strategy can also provide rapid access to pyrido[3,4-b]indoles, trans-2-olefins, and eneamides bearing various functional groups with high regio- and stereoselectivity
公开了一种由钯催化的长链烯烃双键异构化和随后由 B 2 (OH) 2促进的分子内环化合成芳族氧杂杂环的有效串联方法。该策略还可以快速获得具有高区域和立体选择性的各种官能团的吡啶并[3,4- b ]吲哚、反式-2-烯烃和烯酰胺。