title: Nitrone Directing Groups in Rhodium(III)-Catalyzed C-H Activation of Arenes: 1,3-Dipoles versus Traceless Directing Groups.
abstract: Functionalizable directing groups (DGs) are highly desirable in C-H activation chemistry. The nitrone DGs are explored in rhodium(III)-catalyzed C-H activation of arenes and couplings with cyclopropenones. N-tert-butyl nitrones bearing a small ortho substituent coupled to afford 1-naphthols, where the nitrone acts as a traceless DG. In contrast, coupling of N-tert-butyl nitrones bearing a bulky ortho group follows a C-H acylation/[3+2] dipolar addition pathway to give bicyclics. The coupling of N-arylnitrones follows the same acylation/[3+2] addition process but delivers different bicyclics.
authors.affiliation: Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China.
authors.forename: Fang
authors.initials: F
authors.lastname: Xie
authors.affiliation: Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China.
authors.forename: Songjie
authors.initials: S
authors.lastname: Yu
authors.affiliation: Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China.
authors.forename: Zisong
authors.initials: Z
authors.lastname: Qi
authors.affiliation: Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China.
authors.forename: Xingwei
authors.initials: X
authors.lastname: Li
keywords: C−H activation; arenes; reaction mechanisms; rhodium; small ring compounds