Nickel-Catalyzed Sonogashira C(sp)–C(sp<sup>2</sup>) Coupling through Visible-Light Sensitization
作者:Da-Liang Zhu、Ruijie Xu、Qi Wu、Hai-Yan Li、Jian-Ping Lang、Hong-Xi Li
DOI:10.1021/acs.joc.0c01177
日期:2020.7.17
efficient method for visible-light-initiated, nickel-catalyzed Sonogashira C(sp)–C(sp2) coupling has been developed via an energy-transfer mode. Thioxanthen-9-one as a photosensitizer could significantly accelerate the arylation of alkynes with a wide range of (hetero)aryl halides in high yields. The cross-couplingreaction undergoes the stepwise oxidative addition of an arylhalide to nickel(0), transmetalation
reactions of dibromoalkenes with arylboronic acids using a hydrazone–Cu catalyst system proceeded smoothly under mild conditions to afford the corresponding internal alkyne derivatives in good yields. Furthermore, we also succeeded in the synthesis of o-allyloxy(ethynyl)benzene derivatives, which are known to be effective precursors of various heterocyclic compounds, through this reaction.
Synthesis of
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‐Allyloxy(ethynyl)benzene Derivatives by Cu‐Catalyzed Suzuki–Miyaura‐Type Reaction and Their Transformations into Heterocyclic Compounds
作者:Kohei Watanabe、Takashi Mino、Eri Ishikawa、Miyu Okano、Tatsuya Ikematsu、Yasushi Yoshida、Masami Sakamoto、Kazuki Sato、Kazuhiro Yoshida
DOI:10.1002/ejoc.201700217
日期:2017.4.26
Suzuki–Miyaura-type reactions of o-allyloxy(bromoethynyl)benzenes with arylboronic acids using a hydrazone/Cu catalyst system proceeded smoothly in iPrOH under mild conditions to afford the corresponding o-allyloxy(arylethynyl)benzenederivatives in good yields without decomposition of the allyloxy group. We have further demonstrated that annulation and enyne metathesis of the o-allyloxy(arylethynyl)benzene derivatives
Efficient copper-free Sonogashira coupling of aryl chlorides with palladium on charcoal
作者:Anna Komáromi、Zoltán Novák
DOI:10.1039/b810928a
日期:——
Palladium on charcoal serves as an efficient and reusable solid supported catalyst for the Sonogashira coupling of aryl chlorides with terminal acetylenes in the presence of a bulky, electron-rich biphenyl type ligand (XPhos), without copper co-catalyst.
A palladium-catalyzed decarbonylative alkynylation of amides via C–N bond activation is developed. Compared with the reported Ni/Cu catalyzed reaction, which only proceeded well with silylacetylenes, this transformation was also applicable to both aromatic and aliphatic terminal alkynes, including those bearing functional groups, and thus provided a general and straightforward access to diverse internal