Synthesis of spiro[2.5]octa-4,7-dien-6-one with consecutive quaternary centers <i>via</i> 1,6-conjugate addition induced dearomatization of <i>para</i>-quinone methides
作者:Kuo Gai、Xinxin Fang、Xuanyi Li、Jinyi Xu、Xiaoming Wu、Aijun Lin、Hequan Yao
DOI:10.1039/c5cc06287j
日期:——
An efficient one-pot approach for the synthesis of spiro[2.5]octa-4,7-dien-6-ones by employing para-quinone methides has been developed. The reaction proceeded smoothly in high yields under mild conditions without the use of...
P(NMe<sub>2</sub>)<sub>3</sub>-Mediated Umpolung Spirocyclopropanation Reaction of <i>p</i>-Quinone Methides: Diastereoselective Synthesis of Spirocyclopropane-Cyclohexadienones
作者:Yu-Hua Deng、Wen-Dao Chu、Yun-Han Shang、Ke-Yin Yu、Zhi-Long Jia、Chun-An Fan
DOI:10.1021/acs.orglett.0c02998
日期:2020.11.6
substitution offers a new method for effective access to a series of highly functionalized spirocyclohexadienonyl cyclopropanes having two vicinal quaternary carbons in ≤98% yield and >20:1 dr. Significantly, cyclic and acyclic topological structures of α-keto carbonyls as 1,1-dipole one-carbon synthons have a distinct influence on the stereochemistry of products, showing a reversal of diastereoselectivity