Flow synthesis of annulated 5-aryl-substituted pyridines by tandem intramolecular inverse-electron-demand hetero-/retro-Diels–Alder reaction
作者:Rainer E. Martin、Mario Lenz、Thibaut Alzieu、Johannes D. Aebi、Liliane Forzy
DOI:10.1016/j.tetlet.2013.09.069
日期:2013.12
5-Aryl-substituted annulatedpyridines can be accessed directly from the corresponding acetylene substituted pyrimidines through an intramolecularinverse-electron-demand hetero-/retro-Diels–Alder (ihDA/rDA) reaction cascade carried out in continuousflow. Exploiting this new process, a series of cycloalka[c]pyridines that represent useful building blocks for medicinal chemistry were prepared in good
可以通过连续流动进行的分子内逆电子需求杂-/反-Diels-Alder(ih DA / r DA)反应级联,从相应的乙炔基取代的嘧啶中直接获得5-芳基取代的环已吡啶。利用这种新工艺,一系列cycloalka的[ C ^ ]吡啶表示为药物化学有用积木良好制备用短处理时间优异的产率(<45分钟)。重要的是,利用使流体中的溶剂过热的能力允许用甲苯代替通常使用的高沸点溶剂(例如,硝基苯或氯苯)。
Synthesis of 3-benzylisoquinolines by domino imination/cycloisomerisation of 2-propargylbenzaldehydes
An easy entry to uncommon 2-propargylbenzaldehydes was developed. 2-Propargylbenzaldehydes demonstrated to be suitable building blocks for the synthesis of 3-benzyl isoquinolines by microwave promoted domino imination/cycloisomerisation in the presence of ammonium acetate. A small library of 3-benzyl isoquinolines was obtained in good yields under mild reaction conditions. Two alternative plausible reaction mechanisms are proposed.
Gold(I)-Catalyzed Rearrangement of Propargyl Benzyl Ethers: A Practical Method for the Generation and in Situ Transformation of Substituted Allenes
作者:Benoit Bolte、Yann Odabachian、Fabien Gagosz
DOI:10.1021/ja1020469
日期:2010.6.2
of benzyl propargyl ethers react with a gold(I) catalyst to furnish variously substituted allenes via a 1,5-hydride shift/fragmentation sequence. This transformation is rapid and practical. It can be performed under very mild conditions (room temperature or 60 degrees C) using terminal as well as substituted alkyne substrates bearing a primary, secondary, or tertiary benzyl ether group. The allenes
Scandium‐ or hafnium‐catalyzed [6+1] annulation reactions of 2‐cyano‐1‐propargyl‐ and 2‐alkynyl‐1‐cyanomethyl‐indoles with Reformatsky reagent delivered 8‐ and 9‐substituted‐azepino[1,2‐a]indole amines in good to high yields.
Copper‐Catalyzed Enantio‐, Diastereo‐, and Regioselective [2,3]‐Rearrangements of Iodonium Ylides
作者:Bin Xu、Uttam K. Tambar
DOI:10.1002/anie.201705317
日期:2017.8.7
The first highly enantioselective, diastereoselective, and regioselective [2,3]-rearrangement of iodonium ylides has been developed as a general solution to catalytic onium yliderearrangements. In the presence of a chiral copper catalyst, substituted allylic iodides couple with α-diazoesters to generate metal-coordinated iodonium ylides, which undergo [2,3]-rearrangements with high selectivities (up