title: Stable heteroleptic complexes of divalent lanthanides with bulky pyrazolylborate ligands--iodides, hydrocarbyls and triethylborohydrides.
abstract: The reaction of YbI(2) with KTp(Me2) gives (Tp(Me2))YbI(THF)(2) (1-Yb) as a thermally unstable product. Use of the more hindered KTp(tBu,Me) gave (Tp(tBu,Me))LnI(THF)(n) (Ln = Sm, n = 2, 2-Sm; Ln = Yb, n = 1, 2-Yb). The crystal structures of both these compounds are reported. Adducts with neutral ligands such as pyridines and isonitriles can be prepared and the crystal structures of [(Tp(tBu,Me))YbIL(n)] (L = CN(t)Bu, n = 1; L = 3,5-lutidine, n = 2) are described. 2-Sm can be oxidized using AgBPh(4) to give [(Tp(tBu,Me))SmI(THF)(2)]BPh(4). Compounds 2-Sm and 2-Yb are useful starting materials for the preparation of heteroleptic compounds by metathesis with appropriate potassium reagents. The preparations and characterization of the hydrocarbyls (Tp(tBu,Me))Ln{CH(SiMe(3))(2)} (Ln = Sm, 5-Sm; Yb, 5-Yb) and [(Tp(tBu,Me))Ln{CH(2)(SiMe(3))}(THF)] (Ln = Yb, 6a-Yb) and the triethylborohydrides [(Tp(tBu,Me))Ln(HBEt(3))(THF)(n)] (Ln = Sm, n = 0, 7-Sm; Yb, n = 1, 7-Yb) are reported, as well as the crystal structures of 5-Sm and 5-Yb, and the THF adducts 6a-Yb and [(Tp(tBu,Me))Sm{CH(SiMe(3))(2)}(THF)], 5a-Sm.
authors.affiliation: Department of Chemistry, University of Alberta, Edmonton AB. T6G 2G2, Canada.
authors.forename: X W
authors.initials: XW
authors.lastname: Zhang
authors.forename: Graham H
authors.initials: GH
authors.lastname: Maunder
authors.forename: Stefan
authors.initials: S
authors.lastname: Giessmann
authors.forename: Robert
authors.initials: R
authors.lastname: MacDonald
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Ferguson
authors.forename: Andrew H
authors.initials: AH
authors.lastname: Bond
authors.forename: Robin D
authors.initials: RD
authors.lastname: Rogers
authors.forename: Andrea
authors.initials: A
authors.lastname: Sella
authors.forename: Josef
authors.initials: J
authors.lastname: Takats