Experimental and Theoretical Study on the Regioselective Radical Cyclization Reactions of 1-(<i>o</i>-Alkenylaryl)-2-amido-1-ketones for the Construction of Indeno[2,1-<i>d</i>][1,3]oxazin-9-ones
作者:Shuang-Shuo Niu、Yimin Liu、Yue Zhang、Xing-Chi Li、Jian Gong、Wanjian Ding、Ying Cheng
DOI:10.1021/acs.joc.2c00567
日期:2022.8.5
unprecedented dihydrobenzo[6,7]indeno[2,1-d][1,3]oxazin-7-ones and dihydropyrido[2′,3′:3,4]cyclopenta[1,2-d][1,3]oxazin-9-ones has been achieved by employing o-alkenylnaphthaldehyde and o-alkenylnicotinaldehyde as substrates. The regioselectivity between 5-exo-trig and 6-endo-trig radical cyclization reactions of different 1-(o-alkenylaryl)-2-amido-2-aryl-1-ethanones were elucidated with DFT calculations.
开发了一种简单高效的两步法构建新型 2,4,9a-tri取代-4a,9a-二氢茚并[2,1- d ][1,3]oxazin-9-ones。NHC 催化的邻-烯基苯甲醛与N-酰基芳基亚胺的氮杂苯偶姻反应得到 1-( o -alkenylaryl )-2-amido-2-aryl-1-ethanones,其经过区域选择性 5-exo-trig 自由基环化得到三环稠合杂环产物,收率一般。该合成方法对邻烯基苯甲醛的取代基性质、取代模式和空间位阻具有良好的耐受性。基于该方法,合成了前所未有的二氢苯并[6,7]茚并[2,1- d][1,3]oxazin-7-ones 和 dihydropyrido[2',3':3,4]cyclopenta[1,2 - d ][1,3]oxazin-9-ones 通过使用邻烯基萘醛得到和邻烯基烟醛作为底物。用 DFT 计算阐明了不同 1-( o -alkenylaryl