Oxidative Generation of 1-Nitroalkyl Radicals and Their Addition Reaction to Olefins
作者:Noriyoshi Arai、Koichi Narasaka
DOI:10.1246/bcsj.70.2525
日期:1997.10
1-Nitroalkyl radicals are generated by oxidation of potassium salt of 1-aci-nitroalkanes with ammonium hexanitratocerate(IV). When the oxidation is carried out in the presence of electron-rich olefins, such as silyl enol ethers, intermolecular addition of the radicals onto the olefins proceeds to afford β-nitro ketones, which are further converted to α,β-unsaturated ketones in high yield. Stereoselective
Palladium-Catalyzed Carbocyclizations of Unactivated Alkyl Bromides with Alkenes Involving Auto-tandem Catalysis
作者:Alexander R. O. Venning、Megan R. Kwiatkowski、Joan E. Roque Peña、Brendan C. Lainhart、Akil A. Guruparan、Erik J. Alexanian
DOI:10.1021/jacs.7b06794
日期:2017.8.23
carbocyclization of unactivated alkyl bromides with alkenes is described. This approach uses a commercially available bisphosphine ligand and avoids the use of carbon monoxide atmosphere present in prior studies involving alkyl iodides. Detailed mechanistic studies of the transformation are performed, which are consistent with auto-tandem catalysis involving atom-transfer radical cyclization followed by catalytic
Palladium-Catalyzed Heck-Type Reactions of Alkyl Iodides
作者:Kayla S. Bloome、Rebecca L. McMahen、Erik J. Alexanian
DOI:10.1021/ja2091883
日期:2011.12.21
A palladium-catalyzedHeck-typereaction of unactivated alkyl iodides is described. This process displays broad substrate scope with respect to both alkene and alkyl iodide components and provides efficient access to a variety of cyclic products. The reaction is proposed to proceed via a hybrid organometallic-radical mechanism, facilitating the Heck-type process with alkyl halide coupling partners
The ene and reverse ene-processes occur with ketones, as shown by control experiments and by ESI-MS analysis.
敌对和反向敌对过程发生在酮上,这是通过对照实验和ESI-MS分析所显示的。
Asymmetric synthesis of multifunctional cyclopentanes and cyclohexanes via oxycarbenium ion cyclizations of 5-alkoxy-2(3H)-dihydrofuranones
作者:Edzard M. Geertsema、Chiu W. Leung、Arjan van Oeveren、Auke Meetsma、Ben L. Feringa
DOI:10.1016/0040-4039(95)01475-w
日期:1995.10
Intramolecular nucleophilic additions to oxycarbenium ions derived from 5-alkoxy-2(3)-dihydrofuranones gave substituted cyclopentanes or cyclohexanes in good yields. Stereoselectivity in these reactions was usually very high, while regioselectivity could be improved using silicon containing nucleophiles.