Visible-Light Promoted Distereodivergent Intramolecular Oxyamidation of Alkenes
作者:Xiang Ren、Qihang Guo、Jianhui Chen、Hujun Xie、Qing Xu、Zhan Lu
DOI:10.1002/chem.201603977
日期:2016.12.23
The visible‐light‐promoted diastereodivergent intramolecular oxyamination of alkenes is described to construct oxazolindinones, pyrrolidinones and imidazolidones via mild generation of primary amidyl radicals from functionalized hydroxylamines. A unique phenomenon of highly diastereoselective ring‐opening of aziridines controlled by electron sacrifices was observed. Highly diastereoselective amino
描述了可见光促进的烯烃的非对映异构分子内氧胺化反应,可通过温和地从官能化的羟胺生成伯酰胺基来构建恶唑啉酮,吡咯烷酮和咪唑烷酮。观察到一种独特的现象,即由电子牺牲控制的氮丙啶的高度非对映选择性开环。通过该方案,以克为单位有效地获得了高度非对映选择性的氨基醇衍生物。机理研究表明,可分离的抗氮丙啶中间体是由伯酰胺基快速生成的,非对映选择性是由电子牺牲的p K a值控制的。
Copper-Catalyzed Tethered Aziridination of Unsaturated <i>N-</i>Tosyloxy Carbamates
作者:Renmao Liu、Steven R. Herron、Steven A. Fleming
DOI:10.1021/jo0705014
日期:2007.7.1
nitrene addition to alkenes. The carbamate group was used as the tether between the alkene and the nitrene. Subsequent nucleophilic attack of the aziridine was accomplished using RSH, R2NH, N3-, or ROH as the nucleophile. This addition was found to be regio- and stereoselective. This methodology has been used to demonstrate its utility in the regio- and stereoselectivesynthesis of a 1,2-diamino-3-hydroxycyclohexane
Intramolecular Carbonyl Nitroso Ene Reaction Catalyzed by Iron(III) Chloride/Hydrogen Peroxide as an Efficient Tool for Direct Allylic Amination
作者:Duncan Atkinson、Mikhail A. Kabeshov、Mark Edgar、Andrei V. Malkov
DOI:10.1002/adsc.201100632
日期:2011.12
A mild, simple oxidation protocol employing iron(III) chloride as a catalyst and hydrogen peroxide as a stoichiometric oxidant was found to be compatible with an intramolecular carbonyl nitroso ene reaction and allowed us to efficiently convert hydroxamic acids into a diverse range of 1,2- and 1,3-amino alcohol derivatives in a single operation.
copper-catalyzed aerobic oxidative azo-ene cyclization has been developed. The developed CuI/DMAP/O2 system efficiently facilitates the aerobic oxidation of ene-containing hydrazides to azo compounds, which undergo azo-ene cyclizations for the synthesis of oxazolidinones. In addition, the present approach enables the synthesis of lactams, as well as a nitroso-ene cyclization. Preliminary mechanistic
A very mild and selective method for O-benzoylation of hydroxamic acids
作者:Yongsheng Zheng、Muqiong Liu、Yu Yuan
DOI:10.1016/j.tetlet.2014.06.009
日期:2014.7
Selective O-benzoylation of hydroxamic acids is achieved by the treatment of BPO and DABCO. Aliphaticalcohols are not reactive under these conditions. Various radical or oxidation sensitive functional groups are compatible with this protocol, and no anhydrous reagents or solvents are required for the high yields of the benzoylations.