title: Trapping of anionic organic radicals by (TpMe2)2Ln (Ln = Sm, Eu).
abstract: Stoichiometric reaction of [ Sm(Tp(Me2))2 ], 1, with a variety of reducible ketone- and quinone-type substrates gave thermally stable, isolable radical anions/ketyls in moderate to good yields. Thus reaction with benzophenone gave [Sm(Tp(Me2))2(OCPh2)], 2, with fluorenone [Sm(Tp(Me2))2(eta1-OC13H8)], 3, and di-tert-butylparaquinone [Sm(Tp(Me2))2(eta1-OC6H2(tBu)2O)], 4, each of which was structurally characterized. In the case of the less-hindered benzoquinone, an unimetallic semiquinone [Sm(Tp(Me2))2(OC6H4O)], 5, could be isolated, although it was unstable with respect to formation of the dimetallic complex [Sm(Tp(Me2))2]2(mu-OC6H4O), 6. Compound 6 was structurally characterized, as was its anthraquinone analogue [Sm(Tp(Me2))2]2(mu-OC14H8O), 7. When the analogous reaction was carried out between the less-reducing [Eu(Tp(Me2))2] and benzoquinone, only the europium analogue of the semiquinone 5, [Eu(Tp(Me2))2(OC6H4O)], 8, could be isolated. The use of the sterically hindered 3,5-di-tert-butyl-o-benzoquinone allowed isolation of [Sm(Tp(Me2))2(DTBSQ)], 9.
authors.affiliation: Departamento de Química, ITN, Estrada Nacional 10, Sacavém, Portugal.
authors.forename: Angela
authors.initials: A
authors.lastname: Domingos
authors.forename: Irene
authors.initials: I
authors.lastname: Lopes
authors.forename: João C
authors.initials: JC
authors.lastname: Waerenborgh
authors.forename: Noémia
authors.initials: N
authors.lastname: Marques
authors.forename: G Y
authors.initials: GY
authors.lastname: Lin
authors.forename: X W
authors.initials: XW
authors.lastname: Zhang
authors.forename: Josef
authors.initials: J
authors.lastname: Takats
authors.forename: Robert
authors.initials: R
authors.lastname: McDonald
authors.forename: Anna C
authors.initials: AC
authors.lastname: Hillier
authors.forename: Andrea
authors.initials: A
authors.lastname: Sella
authors.forename: Mark R J
authors.initials: MR
authors.lastname: Elsegood
authors.forename: Victor W
authors.initials: VW
authors.lastname: Day