Abstractmagnified imageDescribed herein is the development of a palladium(II)‐catalyzed two‐ or three‐component reaction of 2‐(1‐alkynyl)‐2‐alken‐1‐ones with nucleophiles and allylic chlorides. Various types of nucleophiles such as O‐, N‐, C‐based nucleophiles and olefin‐tethered O‐, N‐, C‐based nucleophiles were investigated. The scope, mechanism and application of this Pd(II)‐catalyzed domino reaction were studied. In these transformations, the palladium catalyst exhibits a dual role, serving simultaneously as a Lewis acid and a transition metal. Two possible reaction pathways (cross‐coupling reaction vs. Heck reaction) from the same intermediate furanylpalladium species were observed. The reaction pathway is dependent on the property of the nucleophile and the length of the tethered chain as well. When olefin‐tethered O‐based nucleophiles were used, only the cross‐coupling reaction pathway was observed, in contrast, both reaction pathways were observed when olefin‐tethered C‐based nucleophiles were employed. The product ratio is dependent on the length of the tethered chain. Furthermore, ring‐closing metathesis (RCM) of corresponding furans with CC bonds provides an easy method for the preparation of functionalized oxygen‐heterocycles – 3,4‐fused bicyclic furans. It is also noteworthy that allylic chloride can be as an oxidant besides its well known function as an alkylating reagent.
Cu(I) Catalyst in DMF: An Efficient Catalytic System for the Synthesis of Furans from 2-(1-Alkynyl)-2-alken-1-ones
作者:Nitin T. Patil、Huanyou Wu、Yoshinori Yamamoto
DOI:10.1021/jo050191u
日期:2005.5.1
The cyclization of 2-(1-alkynyl)-2-alken-1-ones 1 proceeded very smoothly in the presence of alcohols 2 with a catalytic amount of Cu(I)Br in DMF at 80 °C, leading to the formation of highlysubstitutedfurans 3. The catalytic system reported herein is easy to handle, compared to the previously known system wherein the reaction between 1 and 2 needed to use moisture sensitive gold(III) chloride.
AuCl<sub>3</sub>-Catalyzed Synthesis of Highly Substituted Furans from 2-(1-Alkynyl)-2-alken-1-ones
作者:Tuanli Yao、Xiaoxia Zhang、Richard C. Larock
DOI:10.1021/ja0466964
日期:2004.9.1
Highly substituted furans have been synthesized by the reaction of 2-(1-alkynyl)-2-alken-1-ones and various nucleophiles under very mild reaction conditions in good to excellent yields. Gold and some other transition metals are efficient catalysts for this reaction.
Synthesis of Highly Substituted Furans by the Electrophile-Induced Coupling of 2-(1-Alkynyl)-2-alken-1-ones and Nucleophiles
作者:Tuanli Yao、Xiaoxia Zhang、Richard C. Larock
DOI:10.1021/jo0510585
日期:2005.9.1
induced by an electrophile, provides highlysubstitutedfurans in good to excellent yields under very mild reaction conditions. Various nucleophiles, including functionally substitutedalcohols, H2O, carboxylic acids, 1,3-diketones, and electron-rich arenes, and a range of cyclic and acyclic 2-(1-alkynyl)-2-alken-1-ones readily participate in these cyclizations. Iodine, NIS, and PhSeCl have proven
Gold(I)-Catalyzed Reactions between 2-(1-Alkynyl)-2-alken-1-ones and Vinyldiazo Ketones for Divergent Synthesis of Nonsymmetric Heteroaryl-Substituted Triarylmethanes: <i>N-</i> versus <i>C</i>-Attack Paths
作者:Rahul Dadabhau Kardile、Rai-Shung Liu
DOI:10.1021/acs.orglett.0c02765
日期:2020.11.6
Gold-catalyzed synthesis of nonsymmetrical heteroaryl-substitutedtriarylmethanes using 2-(1-alkynyl)-2-alken-1-ones and vinyldiazo ketones is described. In this catalytic sequence, vinyldiazo ketones attack gold-containing 3-furylbenzyl cations to form the observed C(1)-addition products. We also note that vinyldiazo ketones can be thermally cyclized to yield pyrazole derivatives, which can react
Phosphine-Catalyzed Regioselective and Stereoselective Hydrohalogenation Reaction of 2-(1-Alkynyl)-2-alken-1-ones: Synthesis of 2-Halo-1,3-dienes
作者:Wenbo Li、Lihua Gao、Zhenting Yue、Junliang Zhang
DOI:10.1002/adsc.201500408
日期:2015.8.24
A triphenylphosphine (PPh3)‐catalyzed, regioselective and stereoselective hydrohalogenation reaction of 2‐(1‐alkynyl)‐2‐alken‐1‐ones with metal halides in the presence of acetic acid is described, furnishing functionalized 3,4‐disubstituted 2‐halo‐1,3‐dienes in moderate to good yields with high stereoselectivity and regiospecificity. The simple execution, mild conditions and the potential utilization