title: Metal atoms collinear with the spiro carbon of 6,6-open adducts, M2@C80(Ad) (M = La and Ce, Ad = adamantylidene).
abstract: The photochemical reaction of M2@C80 (M = La and Ce) with 2-adamantane-2,3'-[3H]-diazirine (1) affords the corresponding adducts by carbene addition. The adducts were characterized by spectroscopic and single-crystal X-ray structure analyses. Crystallographic data for the adduct La2@C80(Ad) (2, Ad = adamantylidene) reveal that the two La atoms are collinear with the spiro carbon of the 6,6-open adduct. It is noteworthy that the La-La distance is highly elongated by the addition of carbene. Paramagnetic 13C NMR spectral analysis of the adduct Ce2@C80(Ad) (3) indicates that the two Ce atoms are also collinear with the spiro carbon at room temperature in solution. The unique metal positions were confirmed by density functional calculations.
authors.affiliation: Center for Tsukuba Advanced Research Alliance, University of Tsukuba, Tsukuba, Ibaraki 305-8577, Japan.
authors.forename: Michio
authors.initials: M
authors.lastname: Yamada
authors.forename: Chika
authors.initials: C
authors.lastname: Someya
authors.forename: Takatsugu
authors.initials: T
authors.lastname: Wakahara
authors.forename: Takahiro
authors.initials: T
authors.lastname: Tsuchiya
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Maeda
authors.forename: Takeshi
authors.initials: T
authors.lastname: Akasaka
authors.forename: Kenji
authors.initials: K
authors.lastname: Yoza
authors.forename: Ernst
authors.initials: E
authors.lastname: Horn
authors.forename: Michael T H
authors.initials: MT
authors.lastname: Liu
authors.forename: Naomi
authors.initials: N
authors.lastname: Mizorogi
authors.forename: Shigeru
authors.initials: S
authors.lastname: Nagase