Copper-Catalyzed Amino Lactonization and Amino Oxygenation of Alkenes Using <i>O</i>-Benzoylhydroxylamines
作者:Brett N. Hemric、Kun Shen、Qiu Wang
DOI:10.1021/jacs.6b02840
日期:2016.5.11
A copper-catalyzed amino lactonization of unsaturated carboxylic acids has been achieved as well as the analogous intermolecular three-component amino oxygenation of olefins. The transformation features mild conditions and a remarkably broad substrate scope, offering a novel and efficient approach to construct a wide range of amino lactones as well as 1,2-amino alcohol derivatives. Mechanistic studies
Divergent Access to (1,1) and (1,2)‐Azidolactones from Alkenes using Hypervalent Iodine Reagents
作者:Sébastien Alazet、Franck Le Vaillant、Stefano Nicolai、Thibaut Courant、Jerome Waser
DOI:10.1002/chem.201702599
日期:2017.7.18
versatile synthesis of azidolactones through azidation and cyclization of carboxylic acids onto alkenes has been developed. Based on either photoredox or palladium catalysis, (1,1) and (1,2) azido lactones can be selectively synthesized. The choice of catalyst and benziodoxol(on)e reagent serving as azide source was essential to initiate either a radical or Lewis acid mediated process with divergent
Synthesis of Chiral Sulfonyl Lactones via Copper-Catalyzed Asymmetric Radical Reaction of DABCO⋅(SO<sub>2</sub>
)
作者:Yang Wang、Lingling Deng、Jie Zhou、Xiaochen Wang、Haibo Mei、Jianlin Han、Yi Pan
DOI:10.1002/adsc.201701532
日期:2018.3.20
work, an asymmetriccopper‐catalyzed radical multi‐component cascade reaction of an unsaturated carboxylic acid, aryldiazonium tetrafluoroborate, and DABCO⋅(SO2)2 (DABSO) has been developed for the enantioselective synthesis of sulfonyl lactones. In this reaction, this SO2 surrogate, DABSO was applied for the first time in the construction of chiral compounds. This multiple‐step asymmetric radical reaction
Intramolecular Fluorocyclizations of Unsaturated Carboxylic Acids with a Stable Hypervalent Fluoroiodane Reagent
作者:Gemma C. Geary、Eric G. Hope、Alison M. Stuart
DOI:10.1002/anie.201507790
日期:2015.12
A new class of fluorinated lactones was prepared by the intramolecularfluorocyclizations of unsaturatedcarboxylicacids by using the stablefluoroiodanereagent in combination with AgBF4. This unique reaction incorporates a cyclization, an aryl migration, and a fluorination all in one step. The fluoroiodanereagent, prepared easily from fluoride, can also be used without a metal catalyst to give
Photoredox-Catalyzed Cascade Difluoroalkylation and Intramolecular Cyclization for Construction of Fluorinated γ-Butyrolactones
作者:Wanxing Sha、Wenzhong Zhang、Shengyang Ni、Haibo Mei、Jianlin Han、Yi Pan
DOI:10.1021/acs.joc.7b01279
日期:2017.9.15
difluoroalkylation and intramolecular cyclization reaction has been developed for the synthesis of difluoroalkylated oxygen heterocycles. The reaction was carried out under very mild conditions, affording fluorinated isobenzofuran-1-ones, lactone, and cyclic ethers with up to 97% chemical yields. Furthermore, several types of bromofluoroalkane precursors bearing ester, keto, amido, and phosphate groups could all work