Yttrium Dihydride Cation [YH<sub>2</sub>(THF)<sub>2</sub>]<sup>+</sup><sub><i>n</i></sub>: Aggregate Formation and Reaction with (NNNN)-Type Macrocycles
作者:Stefan Arndt、Mathias U. Kramer、Waldemar Fegler、Yumiko Nakajima、Iker Del Rosal、Romuald Poteau、Thomas P. Spaniol、Laurent Maron、Jun Okuda
DOI:10.1021/acs.organomet.5b00422
日期:2015.8.10
Monocationic bis(hydrocarbyl)yttrium complexes [YR2(THF)(2)] [A] (R = CH2SiMe3, CH2C6H4-o-NMe2; A = weakly coordinating anion) underwent hydrogenolysis using dihydrogen or phenylsilane to give a mixture of polynuclear solvent-stabilized dihydride cations [YHz(THF)(2)](n)[A](n). The mixture composition as well as the nudearity n depended on the starting material, solvent, and reaction conditions. NMR spectroscopic data in solution and X-ray diffraction data suggested that the main product was tetranuclear, although conclusive structural data were not obtained. DFT calculations supported a closo-type tetrahedral [YH2(THF)(2)](4)(4+) core. The hydridic character of these cations was revealed by their reaction with benzophenone to give the bis(diphenylmethoxy) cation [Y(OCHPh2)(2)(THF)(4)][AlR4]. The reaction of this cluster with the (NNNN)-type macrocycle Me(4)TACD under dihydrogen gave the dinuclear tetrahydride dication with quadruply bridging hydride ligands, [Y-2(mu-H)(4)(Me(4)TACD)(2)][A](2), analogous to the previously characterized lutetium derivative. NH-acidic (Me(3)TACD)H gave the dinudear dihydride dication [Y-2(mu-H)(2)(Me(3)TACD)(2)(THF)(2)] [A](2).