sequential treatment of an acetylide with a Fischercarbenecomplex and an alkene/diene yields alkynylcyclopropanes with a wide substitution range. The intramolecular process provides 1‐alkynylbicyclo[3.1.0]cyclohexanes by starting from 1,6‐enynes. A non‐heteroatom‐stabilized metal alkynylcarbene is responsible for the selectivetransfer of the propargylene unit.
Visible-light-promoted oxidative halogenation of alkynes
作者:Yiming Li、Tao Mou、Lingling Lu、Xuefeng Jiang
DOI:10.1039/c9cc07655g
日期:——
In nature, halogenation promotes the biological activity of secondary metabolites, especially geminal dihalogenation. Related natural molecules have been studied for decades. In recent years, their diversified vital activities have been explored for treating various diseases, which call for efficient and divergent synthetic strategies to facilitate drug discovery. Here we report a catalyst-free oxidative
Gold-Catalyzed Oxidative Cyclization of 1,5-Enynes Using External Oxidants
作者:Dhananjayan Vasu、Hsiao-Hua Hung、Sabyasachi Bhunia、Sagar Ashok Gawade、Arindam Das、Rai-Shung Liu
DOI:10.1002/anie.201102581
日期:2011.7.18
Golden circle: Two gold‐catalyzed oxidativecyclizations of 1,5‐enynes using 8‐methylquinoline N‐oxide are presented (see example). Experimental results indicate that both reactions proceed through prior oxidation of alkyne to form α‐carbonyl intermediates and subsequent intramolecular carbocyclization.
Gold-Catalyzed Intermolecular Addition of Carbonyl Compounds to 1,6-Enynes: Reactivity, Scope, and Mechanistic Aspects
作者:Mathias Schelwies、Ralph Moser、Adrian L. Dempwolff、Frank Rominger、Günter Helmchen
DOI:10.1002/chem.200901614
日期:2009.10.19
carbonyl compounds to enynes yielding 2‐oxabicyclo[3.1.0]hexanes with four stereogenic centers, is presented. The reaction proceeds with very high diastereoselectivity. The scope of the reaction has been investigated. In addition, experiments and DFT calculations concerning mechanistic aspects were carried out. The reaction course varies with the substitution pattern of the alkene moiety of the starting
完整介绍了最近发现的金(I)催化的反应,即羰基化合物与烯炔的环加成反应,生成带有四个立体异构中心的2-氧杂双环[3.1.0]己烷。反应以非常高的非对映选择性进行。已经研究了反应范围。此外,还进行了有关机械方面的实验和DFT计算。反应过程随起始烯炔的烯烃部分的取代方式而变化。支链烯烃生成2-氧杂双环[3.1.0]己烷;在末端取代的烯烃上引入两个羰基组分,得到六氢环戊[ d ] [1,3]二恶英。
Dihydrobiphenylenes through Ruthenium-Catalyzed [2+2+2] Cycloadditions of<i>ortho</i>-Alkenylarylacetylenes with Alkynes
作者:Silvia García-Rubín、Carlos González-Rodríguez、Cristina García-Yebra、Jesús A. Varela、Miguel A. Esteruelas、Carlos Saá
DOI:10.1002/anie.201309496
日期:2014.2.10
A new synthetic route to dihydrobiphenylenes has been developed. The process involves a mild RuII‐catalyzed [2+2+2] dimerization of ortho‐alkenylarylacetylenes or its more versatile variant, the Ru‐catalyzed [2+2+2] cycloaddition of ortho‐ethynylstyrenes with alkynes. Mechanistic aspects of this [2+2+2] cycloaddition are discussed.