Herein, we describe a convenient and general method for the oxidation of olefins to ketones using either tris(dibenzoylmethanato)iron(III) [Fe(dbm)3] or a combination of iron(II) chloride and neocuproine (2,9-dimethyl-1,10-phenanthroline) as catalysts and phenylsilane (PhSiH3) as additive. All reactions proceed efficiently at room temperature using air as sole oxidant. This transformation has been
Palladium-catalyzed 1,1-alkynylbromination of alkenes with alkynyl bromides
作者:Yusuke Ano、Natsuki Kawai、Naoto Chatani
DOI:10.1039/d1sc02873a
日期:——
The palladium-catalyzed 1,1-alkynylbromination of terminal alkenes with a silyl-protected alkynyl bromide is reported. The method tolerates a diverse range of alkenes including vinylarenes, acrylates, and even electronically unbiased alkene derivatives to afford propargylic bromides regioselectively. Mechanistic studies and DFT calculations indicate that the 1,1-alkynylbromination reaction proceeds
Visible-Light-Enabled <i>Ortho</i>-Selective Aminopyridylation of Alkenes with <i>N</i>-Aminopyridinium Ylides
作者:Yonghoon Moon、Wooseok Lee、Sungwoo Hong
DOI:10.1021/jacs.0c05025
日期:2020.7.15
By utilizing an underexplored reactivity mode of N-aminopyridinium ylides, we developed the visible-light-induced ortho-selective aminopyridylation of alkenes via radical-mediated 1,3-dipolar cycloaddition. The photocatalyzed single-electron oxidation of N-aminopyridinium ylides generates the corresponding radical cations that enable previously inaccessible 1,3-cycloaddition with a broader range of
通过利用 N-氨基吡啶鎓叶立德的未充分探索的反应模式,我们通过自由基介导的 1,3-偶极环加成开发了可见光诱导的烯烃邻位选择性氨基吡啶化。N-氨基吡啶鎓叶立德的光催化单电子氧化产生相应的自由基阳离子,使以前无法实现的1,3-环加成与更广泛的烯烃底物成为可能。所得的环加成加合物迅速进行随后的 NN 键均裂,赋予显着的热力学驱动力以产生各种 β-氨基乙基吡啶。值得注意的是,在无金属和温和条件下,氨基和吡啶基可以通过模块化控制邻位选择性和 1,2- 顺式非对映选择性安装到活化和未活化的烯烃中。
Palladium-Catalyzed Synthesis of Deuterated Alkenes through Deuterodechlorination of Alkenyl Chlorides
of alkenyl chlorides has been developed, and a variety of deuterated alkenes were synthesized with precise control of the deuterium incorporation. This catalytic process tolerates heterocyclic moieties and frameworks derived from bioactive agents. In addition to the double incorporation of deuterium, the gram-scale synthesis of a deuterated iminostilbene unit including a core substructure of carbamazepine
How does it work? Herein, we describe our detailed mechanistic studies on the iron-catalyzedoxidation of olefins to ketones. Isotopic labeling studies (deuterium and 18O) and Mössbauer spectroscopy led to an advanced mechanism for the catalytic cycle.