title: BF3·OEt2-Promoted Synthesis of 2,3-Metallocenocyclohexanones: A 1,2-Hydride Shift and Cationic Cyclization Strategy.
abstract: A BF3·OEt2-promoted cyclization of metallocenyl enones to form cyclohexanone-fused metallocenes is reported. 2,3-Metallocenocyclohexanones were formed exclusively, and no normal Nazarov-type cyclopentanone analogues were detected. The reaction possibly proceeded via an unusual cationic 1,2-hydride shift followed by Friedel-Crafts alkylative cyclization process. During the studies of the alkylation reaction of these keto esters, an unusual and rare facial selectivity was observed. The electrophiles would be attacked from the same face as the second Cp ring.
authors.affiliation: Department of Chemistry, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, P. R. China.
authors.forename: Congfa
authors.initials: C
authors.lastname: He
authors.affiliation: Department of Chemistry, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, P. R. China.
authors.forename: Jie
authors.initials: J
authors.lastname: Wang
authors.affiliation: Department of Chemistry, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, P. R. China.
authors.forename: Zhenhua
authors.initials: Z
authors.lastname: Gu