Cycloaddition of Fluorenone <i>N</i>-Aryl Nitrones with Methylenecyclopropanes and Sequential 1,3-Rearrangement: An Entry to Synthesis of Spirofluorenylpiperidin-4-ones
作者:Xiao-Pan Ma、Jie-Feng Zhu、Si-Yi Wu、Chun-Hua Chen、Ning Zou、Cui Liang、Gui-Fa Su、Dong-Liang Mo
DOI:10.1021/acs.joc.6b02544
日期:2017.1.6
highly selective 1,3-rearrangement to give the desired product. The stereochemistry of the spirofluorenylpiperidin-4-one could be controlled by the cycloaddition and sequential rearrangement strategy. Furthermore, the spirofluorenylpiperidin-4-ones could be not only prepared in one-pot procedure but also converted to useful scaffolds by reduction or oxidation conditions.
Metal free synthesis of 1‐azaspiro[4.4]nonane‐3‐one system via reactions of nitrones with 1,1‐disubstituted allenes
作者:U. Amrutha、Beneesh P.Babu、Sreedharan Prathapan
DOI:10.1002/jhet.3718
日期:2019.12
In the cycloaddition reaction between fluorenone N‐aryl nitrones and 1,1‐disubstituted allenes, the initially formed cycloadduct underwent facile [1,3] shift to give 1′‐phenylspiro[fluorene‐9,2′‐pyrrolidin]‐4′‐ones. Although 1′‐phenylspiro[fluorene‐9,2′‐pyrrolidin]‐4′‐ones are stable in solid state, a few of them underwent facile aerial oxidation in solution to give the corresponding 1′‐phenylspiro[fluorene‐9