Enantioselective Synthesis of Spiroindolines via Cascade Isomerization/Spirocyclization/Dearomatization Reaction
journal contributionposted on 28.01.2020, 16:35 by Zhiqiang Pan, Yuchang Liu, Fengchi Hu, Qinglong Liu, Wenbin Shang, Xu Ji, Chengfeng Xia
The spiroindoline skeleton featured with 2,7-diazaspiro[4.4]nonane exists in various structurally intricate and biologically active monoterpene indole alkaloids. A catalytic asymmetric cascade enamine isomerization/spirocyclization/dearomatization succession to construct the spiroindoline was developed, which employed the indolyl dihydropyridine as a substrate under catalysis of the chiral phosphoric acid. This cascade reaction provided various spiroindolines in both diastereoselective and enantionselective fashions.