title: Highly regioselective derivatization of trimetallic nitride templated endohedral metallofullerenes via a facile photochemical reaction.
abstract: Photochemically generated benzyl radicals react with Sc(3)N@C(80)-I(h) to produce a dibenzyl adduct [Sc(3)N@C(80)(CH(2)C(6)H(5))(2)] in 82% yield and high regioselectivity. The adduct's (1)H spectrum revealed high symmetry: only one AB pattern was observed for the methylene protons. The (13)C NMR spectrum suggested a C(2)-symmetrical structure. DFT calculations reveal that a 1,4-adduct is more favorable than a 1,2-adduct by >10 kcal/mol. The 1,4-structure on [566] ring junctions was unambiguously confirmed by X-ray crystallographic analysis. UV-vis spectra revealed that the removal of two p orbitals from the pi system of the cage together with the benzylic substituents change the electronic properties of the metallofullerene in a manner similar to those reported for disilirane and trifluoromethyl moieties. Under the same conditions from Lu(3)N@C(80)-I(h) we prepared (63% yield) Lu(3)N@C(80)(CH(2)C(6)H(5))(2), which demonstrated properties similar to the 1,4-dibenzyl adduct of Sc(3)N@C(80)-I(h).
authors.affiliation: Department of Chemistry, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24060-0212, USA.
authors.forename: Chunying
authors.initials: C
authors.lastname: Shu
authors.forename: Carla
authors.initials: C
authors.lastname: Slebodnick
authors.forename: Liaosa
authors.initials: L
authors.lastname: Xu
authors.forename: Hunter
authors.initials: H
authors.lastname: Champion
authors.forename: Tim
authors.initials: T
authors.lastname: Fuhrer
authors.forename: Ting
authors.initials: T
authors.lastname: Cai
authors.forename: Jonathan E
authors.initials: JE
authors.lastname: Reid
authors.forename: Wujun
authors.initials: W
authors.lastname: Fu
authors.forename: Kim
authors.initials: K
authors.lastname: Harich
authors.forename: Harry C
authors.initials: HC
authors.lastname: Dorn
authors.forename: Harry W
authors.initials: HW
authors.lastname: Gibson
mesh_terms: D018360:Crystallography, X-Ray; D037741:Fullerenes / Q000737:chemistry*; D008187:Lutetium / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D017672:Nitrogen Compounds / Q000737:chemistry*; D009942:Organometallic Compounds / Q000737:chemistry*; D055668:Photochemical Processes; D012538:Scandium / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet; D013379:Substrate Specificity
chemical_list: D037741:Fullerenes; D017672:Nitrogen Compounds; D009942:Organometallic Compounds; D008187:Lutetium; D012538:Scandium