Ouyang Lu, Qi Chaorong, He Haitao, Peng Youbin, Xiong Wenfang, Ren Yanwei, Jiang Huanfeng
School of Chemistry and Chemical Engineering, State Key Lab of Luminescent Materials and Devices, South China University of Technology , Guangzhou 510640, China.
J Org Chem. 2016 Feb 5;81(3):912-9. doi: 10.1021/acs.joc.5b02487. Epub 2016 Jan 21.
The first base-promoted formal [4 + 3] annulation between 2-fluorophenylacetylenes and ketones has been disclosed. The reaction proceeds through a tandem α-vinylation of ketones followed by an intramolecular nucleophilic aromatic substitution (SNAr) reaction of the in situ generated β,γ-unsaturated ketone intermediates, providing a straightforward access to a wide range of functionalized benzoxepines in moderate to high yields. The transition-metal-free methodology featured a wide substrate scope, the use of easily available starting materials, and a high functional group tolerance.
首次公开了在2-氟苯乙炔与酮之间基于碱促进的形式上的[4 + 3]环化反应。该反应通过酮的串联α-乙烯基化反应进行，随后原位生成的β,γ-不饱和酮中间体发生分子内亲核芳香取代（SNAr）反应，以中等到高的产率直接合成了多种功能化的苯并氧杂环庚三烯。这种无过渡金属的方法具有底物范围广、使用易于获得的起始原料以及高官能团耐受性的特点。
