Indium(III)-Catalyzed Stereoselective Synthesis of Tricyclic Frameworks by Cascade Cycloisomerization Reactions of Aryl 1,5-Enynes
作者:Ramón E. Millán、Jaime Rodríguez、Luis A. Sarandeses、Enrique Gómez-Bengoa、José Pérez Sestelo
DOI:10.1021/acs.joc.1c00825
日期:2021.7.16
The indium(III)-catalyzed cascade cycloisomerizationreaction of 1,5-enynes with pendant aryl nucleophiles is reported. The reaction proceeds in cascade under mild reaction conditions, using InI3 (5 mol %) as a catalyst with a range of 1,5-enynes furnished with aryl groups (phenyl and phenol) at alkene (E and Z isomers) and with terminal and internal alkynes. Using 1-bromo-1,5-enynes, a one-pot sequential
报道了铟 (III) 催化的 1,5-烯炔与芳基亲核试剂的级联异构化反应。该反应在温和的反应条件下级联进行,使用 InI 3 (5 mol %) 作为催化剂,其中一系列 1,5-烯炔在烯烃(E和 Z 异构体)上带有芳基(苯基和苯酚)并带有末端和内部炔烃。使用 1-溴-1,5-烯炔,开发了一种一锅序序铟催化环异构化和钯催化与三有机铟试剂的交叉偶联。双环化是立体有择的,通过仿生级联阳离子-烯烃通过 1,5-烯炔环化(6-endo - dig) 和随后的 C-C 加氢芳基化或 C-O 苯氧基环化。1,5-烯炔基芳基醚的密度泛函理论 (DFT) 计算研究支持两步机制,其中第一个立体选择性 1,5-烯炔环化产生非经典碳正离子中间体,通过 S E Ar 机制演化为三环反应产物. 使用这种方法,可以高效地合成各种三环杂环,如苯并[ b ]色烯、菲啶、呫吨和螺杂环化合物,并具有高原子经济性。
A general catalytic reaction sequence to access alkaloid-inspired indole polycycles
作者:Adithi Danda、Kamal Kumar、Herbert Waldmann
DOI:10.1039/c5cc01555c
日期:——
A general two-step catalytic reaction sequence affording a range of indole alkaloid-inspired complex molecular frameworks is presented.
提供了一种通用的两步催化反应序列,可以得到一系列受吲哚生物碱启发的复杂分子结构。
Synthesis of Farnesol Analogues Containing Triazoles in Place of Isoprenes through ‘Click Chemistry’
作者:H. Spielmann、Thangaiah Subramanian、Sean Parkin
DOI:10.1055/s-0031-1290461
日期:——
A solid-phase three-component Huisgen reaction has been used to generate polar farnesol and farnesyl diphosphate analogues. The Cu(I)-catalyzed 1,3-cycloadditions of various azides with solid supported (E)-3-methylhept-2-en-6-yn-1-ol provided only the 1,4-disubstituted 1,2,3-triazole regioisomers. The organic azides were generated in situ to minimize handling of potentially explosive azides. We have employed this powerful 'click chemistry' to make farnesol analogues where both beta- and gamma-isoprenes were replaced by triazole and substituted aromatic rings, respectively.
Useful Catalytic Enantioselective Cationic Double Annulation Reactions Initiated at an Internal π-Bond: Method and Applications
作者:Karavadhi Surendra、Goreti Rajendar、E. J. Corey
DOI:10.1021/ja4125093
日期:2014.1.15
The 1:1 complex of o,o'-dichloro-R-BINOL and SbCl5 initiates the enantioselective cationic polycyclization of polyunsaturated substrates at a predictable pi-bond which may be either terminal or, as shown herein, internal. The extension of this powerful construction to internal pi-bonds expands the scope of this method and opens up very short pathways to numerous chiral polycyclic molecules, including natural products and their analogues. Especially simple synthetic routes are disclosed that provide access to dysideapalaunic acid, dehydroabietic acid, and epipodocarpic acid and illustrate, the value of this enantioselective approach.
Total synthesis of dl-sirenin
作者:Elias J. Corey、Kazuo Achiwa、John A. Katzenellenbogen