Perfluoro-tagged, phosphine-free palladium nanoparticles supported on silica gel: application to alkynylation of aryl halides, Suzuki–Miyaura cross-coupling, and Heck reactions under aerobic conditions
cross-coupling, as well as in the Heck reaction between methyl acrylate and aryl iodides is described. The reactions are carried out under aerobic and phosphine-free conditions with excellent to quantitative product yields in each case. The catalysts are easily recovered and reused several times without significant loss of activity. The alkynylation of aryl halides (under copper-free conditions) and the Suzuki–Miyaura
Alkynylation of aryl halides with perfluoro-tagged palladium nanoparticles immobilized on silica gel under aerobic, copper- and phosphine-free conditions in water
The utilization of perfluoro-tagged palladium nanoparticles immobilized on fluorous silica gel through fluorous–fluorous interactions (Pdnp-A/FSG) or linked to silica gel by covalent bonds (Pdnp-B) in the alkynylation of terminal alkynes with aryl halides under aerobic, copper- and phosphine-free conditions in water, and their recovery and re-utilization, is described.
Dual gold/photoredox-catalyzed C(sp)–H arylation of terminal alkynes with diazonium salts
作者:Adrian Tlahuext-Aca、Matthew N. Hopkinson、Basudev Sahoo、Frank Glorius
DOI:10.1039/c5sc02583d
日期:——
The arylation of alkyl and aromatic terminal alkynes by a dual gold/photoredoxcatalytic system is described. Using aryldiazonium salts as readily available aryl sources, a range of diversely-functionalized arylalkynes could be synthesized under mild, base-free reaction conditions using visible light from simple household sources or even sunlight. This process, which exhibits a broad scope and functional
描述了金/光氧化还原双催化系统对烷基和芳族末端炔烃的芳基化。使用芳基重氮盐作为容易获得的芳基源,可以使用来自简单家庭来源的可见光甚至阳光,在温和、无碱的反应条件下合成一系列不同官能化的芳基炔。该过程表现出广泛的范围和官能团耐受性,将双金/光氧化还原催化的转化范围扩大到涉及 C-H 键功能化的转化范围,并证明了该概念在以下条件下获得 Au I / Au III氧化还原化学的潜力:温和的氧化还原中性条件。
作者:Jong-Ho Kim、Dong-Ho Lee、Bong-Hyun Jun、Yoon-Sik Lee
DOI:10.1016/j.tetlet.2007.08.015
日期:2007.10
A core-shell type of polymer-supported N-heterocyclic carbene (NHC) palladium catalyst was applied to Sonogashira cross-coupling reactions without copper cocatalyst under ambient atmosphere. This supported NHC–palladium complex efficiently catalyzed the copper-free Sonogashira reaction of various aryliodides and bromides with terminal alkynes; the reaction exhibited high dependency on the temperature
tri-palladium clusters [Pd3]+ were successfully applied in the catalytic Sonogashira and Heck couplings. For both reactions, these palladium triangles showed excellent reactivities even in gram-scale syntheses and presented exclusive selectivity to aryl iodides over the other halogenated aromatics. HRMS tracking of [Pd3]+ in both reactions revealed their robustness.