The direct alkenylation of C(sp3)âH bonds was achieved by employing benzophenone and 1,2-bis(phenylsulfonyl)ethylene under photo-irradiation conditions. This simple metal-free reaction enables the substitution of heteroatom-substituted methine, methylene and aliphatic C(sp3)âH bonds by (E)-sulfonylalkene units in a highly chemoselective manner. The derived sulfonylalkenes were further converted in a single step to the prenyl derivatives via a second photo-induced radical substitution and to the pyrrole derivatives via cyclization and aromatization steps. The present protocol thus serves as an efficient method for the direct extension of carbon skeletons for the synthesis of structurally complex natural products and pharmaceuticals.
This works introduces hypervalent bis‐catecholato silicon compounds as versatile sources of alkylradicalsuponvisible‐lightphotocatalysis. Using Ir[(dF(CF3)ppy)2(bpy)](PF6) (dF(CF3)ppy=2‐(2,4‐difluorophenyl)‐5‐trifluoromethylpyridine, bpy=bipyridine) as catalytic photooxidant, a series of alkylradicals, including highly reactive primary ones can be generated and engaged in various intermolecular
Boronic Acid Mediated Carbocyanation of Olefins and Vinylation of Alkyl Iodides
作者:Reina Hara、Chahinaz Khiar、Nitin S. Dange、Pierre Bouillac、Frédéric Robert、Yannick Landais
DOI:10.1002/ejoc.201800444
日期:2018.8.15
The tin‐free carbocyanation of olefins and the addition of alkyliodides to vinylsulfones were developed by using phenylboronic acid as an aryl radical precursor and tin surrogate. The resulting aryl radical then selectively abstracted an iodineatom from the alkyliodide to generate a radical that was employed in C–C bond forming processes.
Reactions of alkylmercurials with heteroatom-centered acceptor radicals
作者:Glen A. Russell、Preecha. Ngoviwatchai、Hasan I. Tashtoush、Anna. Pla-Dalmau、Rajive K. Khanna
DOI:10.1021/ja00219a030
日期:1988.5
En particulier, reactivite relative de chlorures d'alkylmercures vis-a-vis de PhS • , PhSe • et I • generes a partir du disulfure de phenyle, diseleniure de phenyle et du β-iodo styrene ou du (diphenyl-1,1 iodo-2) ethylene
En 特别,反应性相对于 de PhS • , PhSe • et I • 与 de PhS • , PhSe • et I • 属 a partir du disulfure de phenyle, diseleniure de phenyle et du β-iodo 苯乙烯 ou du (diphenyl-1,1 iodo -2) 乙烯
Aryl Radical‐Mediated Alkenylation of Alkyl Halides
The free‐radical alkenylation of a range of alkyl iodides with a vinyldisulfones has been carried out, leading to the desired vinylsulfones in moderate to good yields under mild conditions. The process is initiated by an aryl radical which abstracts the iodine atom from the alkyl iodide to form a C‐centered radical intermediate, the addition of which onto the vinyldisulfone providing the final vinylsulfone