Metal- and Protection-Free [4 + 2] Cycloadditions of Alkynes with Azadienes: Assembly of Functionalized Quinolines
作者:Rakesh K. Saunthwal、Monika Patel、Akhilesh K. Verma
DOI:10.1021/acs.orglett.6b00817
日期:2016.5.6
A base promoted, protection-free, and regioselective synthesis of highly functionalized quinolines via [4 + 2] cycloaddition of azadienes (generated in situ from o-aminobenzyl alcohol) with internal alkynes has been discovered. The reaction tolerates a wide variety of functional groups which has been successfully extended with diynes, (2-aminopyridin-3-yl)methanol, and 1,4-bis(phenylethynyl)benzene
已发现通过氮杂二烯[4 + 2](由邻氨基苄醇原位生成)与内部炔烃的环加成反应,可促进高度官能化的喹啉的碱促进,无保护和区域选择性的合成。该反应可耐受多种官能团,这些官能团已成功地用二炔,(2-氨基吡啶-3-基)甲醇和1,4-双(苯基乙炔基)苯扩展,得到了(Z)-苯基-2-苯乙烯基喹啉,分别是苯基萘啶和炔烃取代的喹啉。分离出的氮杂二烯中间体和氘标记研究很好地支持了所提出的机理和溶剂的重要作用。