Reductive Decarboxylative Alkynylation of
<i>N</i>
‐Hydroxyphthalimide Esters with Bromoalkynes
作者:Liangbin Huang、Astrid M. Olivares、Daniel J. Weix
DOI:10.1002/anie.201706781
日期:2017.9.18
A new method for the synthesis of terminal and internal alkynes from the nickel‐catalyzed decarboxylative coupling of N‐hydroxyphthalimide esters and bromoalkynes is presented. This reductivecross‐electrophilecoupling is the first to use a C(sp)−X electrophile, and appears to proceed via an alkynylnickel intermediate. The internal alkyne products are obtained in yields of 41–95 % without the need
Highly Selective <i>Syn</i>
Addition of 1,3-Diones to Internal Ynamides Catalyzed by Zinc Iodide
作者:Rémi Plamont、Lionel V. Graux、Hervé Clavier
DOI:10.1002/ejoc.201701690
日期:2018.3.22
used as nucleophiles to perform additions to ynamides, highly selective hydroalkoxylation of internal ynamides is now described herein. Several catalytic systems were compared to carry out this transformation including transition metal-based catalysts or Lewis acids. ZnI2 was found to be both very active and highly selective giving only E adducts through a syn addition. Scope and limits investigation
Copper(II)-Catalyzed Amidations of Alkynyl Bromides as a General Synthesis of Ynamides and <i>Z</i>-Enamides. An Intramolecular Amidation for the Synthesis of Macrocyclic Ynamides
作者:Xuejun Zhang、Yanshi Zhang、Jian Huang、Richard P. Hsung、Kimberly C. M. Kurtz、Jossian Oppenheimer、Matthew E. Petersen、Irina K. Sagamanova、Lichun Shen、Michael R. Tracey
DOI:10.1021/jo060230h
日期:2006.5.1
method for the coupling of a wide range of amides with alkynyl bromides is described here. This novel amidation reaction involves a catalytic protocol using copper(II) sulfate-pentahydrate and 1,10-phenanthroline to direct the sp-C−N bond formation, leading to a structurally diverse array of ynamides including macrocyclic ynamides via an intramolecular amidation. Given the surging interest in ynamide chemistry
Homogeneous and Nanoparticle Gold-Catalyzed Hydrothiocyanation of Haloalkynes
作者:Xiaojun Zeng、Bocheng Chen、Zhichao Lu、Gerald B. Hammond、Bo Xu
DOI:10.1021/acs.orglett.9b00728
日期:2019.4.19
homogeneous and heterogeneous nanoparticle gold-catalyzed addition of sulfur nucleophiles to alkynes was developed. More specifically, gold-catalyzed hydrothiocyanation of haloalkynes gave good yields and good stereoselectivity of vinyl thiocyanates. Furthermore, a sulfur-based gold catalyst (PPh3AuSCN) has shown a unique reactivity in gold-catalyzed reactions such as the cyclization of N-propargylic amides
A robust and regioselective PdII-catalyzed haloalkynylation of haloalkynes has been established under ligand-free and oxidant-free conditions. Careful selection of the haloalkyne starting material, with respect to electron densities of the alkyne, allows for strong control of the order and selectivity of the halide atoms in the coupled product.