Synthesis of Diaryl Ethers, Diaryl Sulfides, Heteroaryl Ethers and Heteroaryl Sulfides under Microwave Dielectric Heating
作者:Quanrui Wang、Feng Li、Qingqing Meng、Huansheng Chen、Zhiming Li、Fenggang Tao
DOI:10.1055/s-2005-865321
日期:——
This paper describes the synthesis of diaryl ethers and sulfides by utilizing microwave heating methodology. The methodology is shown to be rapid and efficient for the coupling of phenols or thiophenol with electron-deficient aryl halides through a SNAr reaction. The scope of the protocol can be expanded to six-membered heterocycles bearing a hydroxyl group as well as to the reaction of 2-pyrimidinethiol with mildly activated aryl halides, providing heteroaryl ethers and sulfides, respectively. The advantages of the present method include the wide substrate scope, the obviation of metal catalysts, ease of product isolation, and high purity of products.
Diaryl ether synthesis in supercritical carbon dioxide in batch and continuous flow modes
作者:Jin-Kyun Lee、Matthew J. Fuchter、Rachel M. Williamson、Gary A. Leeke、Edward J. Bush、Ian F. McConvey、Simon Saubern、John H. Ryan、Andrew B. Holmes
DOI:10.1039/b808374f
日期:——
A high yielding, batch mode synthesis of diaryl ethers and sulfides by an SNAr fluoride-mediated process in scCO2 has been developed; the use of a polymer-supported imidazolium fluoride reagent in batch mode led to the development of a fixed-bed continuous flow process, with high conversions.
P(i-BuNCH2CH2)3N: an efficient promoter for the microwave synthesis of diaryl ethers
作者:Steven M. Raders、John G. Verkade
DOI:10.1016/j.tetlet.2008.03.089
日期:2008.5
of aryl fluorides with aryl TBDMS ethers under microwave conditions gave moderate to high yields of the desired products at low catalyst loadings and in short times. In this methodology, electron deficient aryl fluorides possessing substituents, such as nitro, cyano, and ester, were coupled with sterically demanding aryl TBDMS ethers as well as with aryl TBDMS ethers bearing a variety of functionalities
P(<i>i</i>-BuNCH<sub>2</sub>CH<sub>2</sub>)<sub>3</sub>N: An Efficient Promoter for the Nucleophilic Aromatic Substitution Reaction of Aryl Fluorides with Aryl TBDMS (or TMS) Ethers
作者:Sameer Urgaonkar、John G. Verkade
DOI:10.1021/ol051108s
日期:2005.7.1
[reaction: see text]. The nucleophilic aromatic substitution reaction between electron-deficient aryl fluorides and aryl TBDMS (or TMS) ethers has been shown to be efficiently promoted by proazaphosphatranes such as P(i-BuNCH(2)CH(2))(3)N (3). Excellent yields of diaryl ether products were obtained under unusually mild conditions.
Synthesis of Diaryl Ethers, Diaryl Thioethers, and Diarylamines Mediated by Potassium Fluoride−Alumina and 18-Crown-6: Expansion of Scope and Utility<sup>1</sup>
作者:J. Scott Sawyer、Elisabeth A. Schmittling、Jayne A. Palkowitz、William J. Smith
DOI:10.1021/jo980800g
日期:1998.9.1
An efficient alternative to the Ullmann ether synthesis of diaryl ethers, diaryl thioethers, and diarylamines involving the SNAr addition of a phenol, thiophenol, or aniline to an appropriate aryl halide, mediated by potassium-fluoride alumina and 18-crown-6 in acetonitrile or DMSO, is described. Expansion of the reaction conditions to include DMSO as solvent has resulted in a far greater range of substitution patterns permitted on the electrophile. For example, it was found that electronically unfavorable S-chlorobenzonitrile could be condensed with 3-methoxyphenol to form the corresponding diaryl ether in 66% yield, a combination not normally amenable to Ullmann coupling. Electron-withdrawing groups present on the electrophile may be as diverse as nitro, cyano, formyl, acetyl, ester, amide, and even aryl. The method features a simple reaction procedure that provides products in generally good to excellent purified yields.