Yang Lu, Matsuyama Hidenori, Zhang Sheng, Terada Masahiro, Jin Tienan
Department of Chemistry, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan.
State Key Laboratory of Fine Chemicals and School of Chemistry, Dalian University of Technology, Dalian 116023, China.
Org Lett. 2020 Jul 2;22(13):5121-5125. doi: 10.1021/acs.orglett.0c01725. Epub 2020 Jun 18.
A novel tandem single-electron oxidative ring expansion reaction has been developed for the construction of the saddle-shaped polycyclic arenes fused with cyclooctatetraene, that is, dibenzo[3,4:7,8]cycloocta[1,2-]phenanthrenes (dbCOTPs). The combination of Cu(OTf) catalyst with DDQ triggered the selective oxidation of -biphenyl-tethered methylenecirculenes fused with a seven-membered ring, giving rise to the formation of the corresponding eight-membered ring fused dbCOTPs. The present tandem ring expansion of a seven- to an eight-membered ring takes place via the selective single-electron oxidation of the benzylidene moiety, intramolecular spirocyclization, and 1,2-aryl migration sequence.
一种新型的串联单电子氧化环扩展反应已被开发出来，用于构建与环辛四烯稠合的鞍形多环芳烃，即二苯并[3,4:7,8]环辛并[1,2-]菲（dbCOTP）。Cu(OTf)催化剂与DDQ的组合引发了与七元环稠合的联苯连接亚甲基环烯的选择性氧化，从而形成了相应的与八元环稠合的dbCOTP。目前从七元环到八元环的串联环扩展是通过亚苄基部分的选择性单电子氧化、分子内螺环化和1,2-芳基迁移序列进行的。
