title: Oxidatively Triggered Carbon-Carbon Bond Formation in Ene-amide Complexes.
abstract: Ene-amides have been explored as ligands and substrates for oxidative coupling. Treatment of CrCl2, Cl2Fe(PMe3)2, and Cl2Copy4 with 2 equiv of {(2,6-(i)Pr2C6H3)(1-(c)Hexenyl)N}Li afforded pseudosquare planar {η(3)-C,C,N-(2,6-(i)Pr2C6H3)(1-(c)Hexenyl)N}2Cr (1-Cr, 78%), trigonal {(2,6-(i)Pr2C6H3)(1-(c)Hexenyl)N}2Fe(PMe3) (2-Fe, 80%), and tetrahedral {(2,6-(i)Pr2C6H3)(1-(c)Hexenyl)N}2Co(py)2 (3-Co, 91%) in very good yields. The addition of CrCl3 to 1-Cr, and FeCl3 to 2-Fe, afforded oxidatively triggered C-C bond formation as rac-2,2'-di(2,6-(i)Pr2C6H3N═)2dicyclohexane (EA2) was produced in modest yields. Various lithium ene-amides were similarly coupled, and the mechanism was assessed via stoichiometric reactions. Some ferrous compounds (e.g., 2-Fe, FeCl2) were shown to catalyze C-arylation of {(2,6-(i)Pr2C6H3)(1-(c)Hexenyl)N}Li with PhBr, but the reaction was variable. Structural characterizations of 1-Cr, 2-Fe, and 3-Co are reported.
authors.affiliation: Department of Chemistry & Chemical Biology, Baker Laboratory, Cornell University , Ithaca, New York 14853, United States.
authors.forename: Brian P
authors.initials: BP
authors.lastname: Jacobs
authors.affiliation: Department of Chemistry & Chemical Biology, Baker Laboratory, Cornell University , Ithaca, New York 14853, United States.
authors.forename: Peter T
authors.initials: PT
authors.lastname: Wolczanski
authors.affiliation: Department of Chemistry & Chemical Biology, Baker Laboratory, Cornell University , Ithaca, New York 14853, United States.
authors.forename: Emil B
authors.initials: EB
authors.lastname: Lobkovsky