title: Planar chirality change in dediazoniation reactions of paracyclophanes and mechanistic implication.
abstract: Dediazoniation reactions of (S(p))-4-bromo-13-[2.2]paracyclophanyldiazonium fluoborate 2a through a heterolytic cleavage process gave products with partial racemization. In contrast, dediazoniation reactions of (S(p))-2a undergoing a nonheterolytic cleavage process afforded products with retention of configuration. A key intermediate, the bromonium cation B, caused the racemization. The unexpected racemization allowed the mechanisms of the dediazoniation reaction to be probed.
authors.affiliation: Department of Chemistry, Shandong University, Shanda South Road No. 27, Jinan 250100, P. R. China.
authors.forename: Fuyan
authors.initials: F
authors.lastname: He
authors.forename: Yudao
authors.initials: Y
authors.lastname: Ma
authors.forename: Lei
authors.initials: L
authors.lastname: Zhao
authors.forename: Wenzeng
authors.initials: W
authors.lastname: Duan
authors.forename: Jianqiang
authors.initials: J
authors.lastname: Chen
authors.forename: Chun
authors.initials: C
authors.lastname: Song