Transition-metal-catalyzed cross-coupling reactions between naturally abundant sp3-hybridized carbon centers facilitate access to diverse molecules with complex three-dimensional structures. Organometallic compounds are among one of the most powerful reagents that are broadly used in carbon–carbon bondformations. Although sp2-hybridized organometallic compounds are widely employed in cross-couplings, sp3-hybridized
Synthesis of trisubstituted alkenes by Ni-catalyzed hydroalkylation of internal alkynes with cycloketone oxime esters
作者:Xiao-Yu Lu、Chuang-Chuang Liu、Run-Chuang Jiang、Lu-Yu Yan、Qi-Le liu、Qing-Qing Wang、Jia-Mei Li
DOI:10.1039/d0cc06517j
日期:——
Ni-catalyzed hydroalkylation of internal alkynes with cycloketone oxime esters was developed. The reaction has a broad substrate scope. This hydroalkylation shows excellent regio- and stereo-selectivity. This method enables readily available starting materials to be used to access a range of cyano-substituted single-configuration trisubstituted alkenes. These are valuable feedstock chemicals and are widely
Aqueous Ammonia as a New Activator for Sonogashira Coupling
作者:Mohamed S. Mohamed Ahmed、Akitoshi Sekiguchi、Kentaro Masui、Atsunori Mori
DOI:10.1246/bcsj.78.160
日期:2005.1
Sonogashira coupling, which is a coupling reaction of terminal alkynes with organic halides, takes place with dilute aqueous ammonia as an activator. The reaction of several terminal alkynes and aryl iodides in the presence of small excess of aqueous ammonia at room temperature furnishes the cross-coupling product in good-to-excellent yields. A water-soluble amine with a high boiling point is alternatively employed for reactions at higher temperatures. A related coupling reaction in the presence of carbon monoxide also proceeded at room temperature and under ambient pressure to afford α,β-alkynyl ketones efficiently.
An Efficient Coupling of Aryl Iodides with Terminal Alkynes Catalyzed by Silica-Supported Sulfur Palladium(0) Complex
作者:Ming-Zhong Cai、Cai-Sheng Song、Xian Huang
DOI:10.1080/00397919708006795
日期:1997.6
Abstract A silica - supported sulfur palladium(0) complex was prepared by the direct ligand - exchange reaction of poly - γ - mercaptopropylsiloxane with Pd(PPh3)4. It was an efficient catalyst for the coupling of aryliodides with terminalalkynes.
is driven by a novel activation strategy and features a unique Pd(I)-Pd(I) mechanism, involving an iodide-assisted binuclear step to release the product. This method enables β-selective hydroformylation of a large range of alkenes and alkynes, including sensitive starting materials. Its utility is demonstrated in the synthesis of antiobesity drug Rimonabant and anti-HIV agent PNU-32945. In a broader