Reinventing the De Mayo reaction: synthesis of 1,5-diketones or 1,5-ketoesters <i>via</i> visible light [2+2] cycloaddition of β-diketones or β-ketoesters with styrenes
作者:Rebeca Martinez-Haya、Leyre Marzo、Burkhard König
DOI:10.1039/c8cc07044j
日期:——
reaction between 1,3-diketones and styrenes following a [2+2] cycloaddition pathway via a photosensitization mechanism gives access to 1,5-diketones. The reaction has been applied to substituted styrenes and aryl- and alkyl-substituted ketones. Moreover, the method converts β-ketoesters, β-amido esters, and β-cyano ketones. Seven membered rings, a frequent structural motif of natural products, are also
Oxidative alkylation of alkenes with carbonyl compounds through concomitant 1,2-aryl migration by photoredox catalysis
作者:Zhaowei Lin、Maojian Lu、Boyi Liu、Jing Gao、Mingqiang Huang、Zhenhong Gan、Shunyou Cai
DOI:10.1039/d0nj03733h
日期:——
Visible-light-enabled oxidative radical 1,2-alkylarylation of α-aryl allylic alcohols with carbonylcompounds has been established under mild conditions. An efficient and convenient protocol for the construction of a variety of 1,5-dicarbonyl compounds was realized in the presence of organic fluorophore 4CzIPN, hypervalent iodine(III) reagent, and visible light irradiation. An obvious kinetic isotope
Oxidative radical 1,2-alkylarylation of alkenes with α-C(sp<sup>3</sup>)–H bonds of acetonitriles involving 1,2-aryl migration
作者:Yang Li、Bang Liu、Hai-Bing Li、Qiuan Wang、Jin-Heng Li
DOI:10.1039/c4cc08902b
日期:——
unactivated alkenes with the alpha-C(sp(3))-H bonds of acetonitriles for the synthesis of 5-oxo-pentanenitriles is presented. In the presence of TBPB (tert-butyl peroxybenzoate), a variety of alpha-aryl allylic alcohols underwent the 1,2-alkylarylation reaction with acetonitriles, giving 5-oxo-pentanenitriles in good to excellent yields. This method proceeds via the C(sp(3))-H oxidative coupling with the
Visible-light-induced 1,2-alkylarylation of alkenes with a-C(sp3)–H bonds of acetonitriles involving neophyl rearrangement under transition-metal-free conditions
An efficient visible-light-induced difunctionalization of alkenes with a-C(sp3)–H bonds of nitriles is described for the constructing of diverse 5-oxo-pentanenitriles under transition-metal-free conditions. This protocol proceeds via the functionalization of C(sp3)–H bond and radical addition/intramolecular 1,2-aryl migration processes, which features a wide scope of substituted α,α-diaryl allylic
reactions of gem-bromonitroalkanes with α,α-diaryl allyl alcohol trimethylsilyl ethers was reported. A cascade consisting of visible-light-induced generation of an α-nitroalkyl radical and a subsequent neophyl-typerearrangement was key to realize the coupling reactions. Structurally diverse α-aryl-γ-nitro ketones, especially those bearing a nitrocyclobutyl structure, were prepared in moderate to high