Pd together with CuI has been well known as the catalyst towards Sonogashirareaction, which provides an effective route to functional alkynes. However, the achievement of high activity and selectivity of this catalytic system is still challenging in some cases. Illustrative examples include their low activity for aryl chloride substrates, and switched selectivity to oxidative coupling products in
Pd 与 CuI 一起作为 Sonogashira 反应的催化剂是众所周知的,这为功能性炔烃提供了有效的途径。然而,在某些情况下,实现该催化体系的高活性和选择性仍然具有挑战性。说明性的例子包括它们对芳基氯底物的低活性,以及在空气气氛中对氧化偶联产物的选择性转换。在这项工作中,掺入了 Cu 的 Au 13纳米团簇 [Au 13 Cu 2 (PPh 3 ) 6 (SC 2 H 4 Ph) 6 ] + [NO 3 ] - (Au 13 Cu 2) 是通过快速合成以高产率设计和制备的。这种原子级精确的纳米团簇显示出成为 Sonogashira 反应的新型催化系统的潜力,具有高活性和选择性,以及即使在空气中也具有良好的可回收性。
Gold-catalyzed Fluorination of Alkynyl Esters and Ketones: Efficient Access to Fluorinated 1,3-Dicarbonyl Compounds
作者:Xiaojun Zeng、Zhichao Lu、Shiwen Liu、Gerald B. Hammond、Bo Xu
DOI:10.1002/adsc.201701179
日期:2017.11.23
We developed an efficient synthesis of 2-fluoro-1,3-dicarbonyl compounds using readily available alkynyl ketones or esters as starting material. The key step is the insertion of hydrogen fluoride (HF) to the gold carbene intermediate generated from cationic gold catalyzed addition of N-oxides to alkynyl ketones or esters. This method gives excellent chemical yields and regioselectivity with good functional
Polymethylhydrosiloxane (PMHS) as an Additive in Sonogashira Reactions
作者:Robert E. Maleczka Jr.、William P. Gallagher
DOI:10.1055/s-2003-37522
日期:——
Polymethylhydrosiloxane (PMHS) in combination with CsF facilitates the Sonogashira reaction of a variety of alkynes and electrophiles. These couplings appear to involve the in situ formation and reaction of an alkynylsiloxane. Such couplings can be run amine free at room temperature, reaction times are short, workup is easy, and product purification is straightforward. Thus, the advantages (and disadvantages) of running Sonogashira couplings with 1-silylalkynes are realized, without the need to preform the alkynyl silane.
PMHS-Mediated Couplings of Alkynes or Benzothiazoles with Various Electrophiles: Application to the Synthesis of (−)-Akolactone A
作者:William P. Gallagher、Robert E. Maleczka
DOI:10.1021/jo034463+
日期:2003.8.1
Polymethylhydrosiloxane (PMHS) in combination with CsF facilitates the cross-coupling of alkynes or benzothiazoles with an array of vinyl, styryl, and aryl halides or nonaflates as well as acid chlorides. Experimental and spectroscopic evidence indicates that these reactions involve the in situ generation of a siloxyl intermediate. These cross-couplings proceed relatively quickly at room temperature
Palladium Nanoparticles Immobilized on Chemically Modified Silica Gel: Efficient Heterogeneous Catalyst for Suzuki, Stille and Sonogashira Cross-Coupling Reactions
作者:Piyali Dutta、Amitabha Sarkar
DOI:10.1002/adsc.201100168
日期:2011.10
Nanoparticulate palladium (Pdnp-2) supported on polyethylene glycol-functionalized silica gel is an excellent heterogeneous catalytic system for Suzuki, Sonogashira and Stille cross-coupling reactions that afford products in high yield. The immobilized palladiumnanoparticles were readily prepared by reaction of modified silica gel (1) with potassium tetrachloropalladate(II) in the presence of an acyl