<i>Z</i>-Selective Olefin Synthesis via Iron-Catalyzed Reductive Coupling of Alkyl Halides with Terminal Arylalkynes
作者:Chi Wai Cheung、Fedor E. Zhurkin、Xile Hu
DOI:10.1021/jacs.5b01784
日期:2015.4.22
Selective catalytic synthesis of Z-olefins has been challenging. Here we describe a method to produce 1,2-disubstituted olefins in high Z selectivity via reductive cross-coupling of alkylhalides with terminal arylalkynes. The method employs inexpensive and nontoxic catalyst (iron(II) bromide) and reductant (zinc). The substrate scope encompasses primary, secondary, and tertiaryalkylhalides, and
unexplored area for C−C bond formation. Herein 64 examples of β‐alkylated styrene derivatives, synthesized through the reactions of readily accessible feedstock olefins with β‐nitrostyrenes by ozone/FeII‐mediated radical substitutions, are reported. These reactions proceed with good efficiencies and high stereoselectivities under mild reaction conditions and tolerate an array of functional groups. Also demonstrated
烯烃C(sp 3)-C(sp 2)键的脱烯基烯基化作用一直是C-C键形成的未知区域。本文报道了64个β-烷基化苯乙烯衍生物的例子,这些例子是通过容易获得的原料烯烃与β-硝基苯乙烯通过臭氧/ Fe II介导的自由基取代反应而合成的。在温和的反应条件下,这些反应具有良好的效率和较高的立体选择性,并且可以耐受一系列官能团。还证明了该策略通过产品的几种合成转化以及天然产物异吗啡丁和药物(E)-美丹尼丁的合成的适用性。
Metal-Free Oxidative Decarbonylative Hydroalkylation of Alkynes with Secondary and Tertiary Alkyl Aldehydes
作者:Xuan-Hui Ouyang、Ren-Jie Song、Bang Liu、Jin-Heng Li
DOI:10.1002/adsc.201501113
日期:2016.6.16
A new, metal‐free, radical‐mediated oxidative decarbonylative hydroalkylation of various alkynes with secondary and tertiary alkyl aldehydes using di‐tert‐butyl peroxide (DTBP) as oxidant is presented. This method enables the simultaneous formation of a CC bond and a CH bond through a sequence of decarbonylation, radical addition and protonation, and provides a straightforward route for transforming
Highly selective coupling of organoboron compounds via oxovanadium(V)-induced oxidation
作者:Takuji Ishikawa、Suguru Nonaka、Toshikazu Hirao
DOI:10.1039/a801844h
日期:——
Reaction of organoboranes or organoborane ate complexes (obtained by treatment with BunLi or CsF) with oxovanadium(V) compounds results in the intramolecular oxidative coupling of organic groups on the boranes or borates.
Herein, we report an efficient photoinduced iron-catalyzed strategy for cross-couplings of alkyl carboxylic and acrylic acids, which provides a powerful tool for the synthesis of a variety of alkenes with polar functional groups. This novel synthetic methodology can also be applied to the preparation of ketones by using α-keto acids. Mechanistic experiments revealed preliminary mechanistic details