Yttrium Complexes with Group 13 Heterobenzene-Type Ligands

The yttrium gallabenzene complex [(1-Me-3,5-tBu(2)-C5H3Ga)(mu-Me)Y(2,4-dtbp)] is accessible from Y(GaMe4)(3) and K(2,4-dtbp) via a tandem salt metathesis/methane elimination (2,4-dtbp=2,4-di-tert-butyl-pentadienyl). The pentadienyl ligand in [(1-Me-3,5-tBu(2)-C5H3E)(mu-Me)Y(2,4-dtbp)] (E=Al, Ga) is easily displaced by salt metathesis with KC5Me5 and KTp(Me,Me) (Tp(Me,Me)=tris(pyrazolyl-Me-2-3,5)borato) affording [(1-Me-3,5-tBu(2)-C5H3E)(mu-Me)Y(Tp(Me,Me))] and [(1-Me-3,5-tBu(2)-C5H3E)(mu-Me)Y(C5Me5)]. The yttrium center in [(1-Me-3,5-tBu(2)-C5H3E)(mu-Me)Y(2,4-dtbp)] readily forms adducts with neutral Lewis bases like 4-DMAP (4-dimethylaminopyridine), PMe3, DMPE (1,2-bis(dimethylphosphino)ethane), and DME (1,2-dimethoxyethane). In stark contrast, addition of TMEDA (N,N,N',N'-tetramethylethylenediamine) results in methyl/pentadienyl exchange between aluminum and yttrium resulting in [(1-(2,4-dtbp)-1-Me-3,5-tBu(2)-C5H3Al)Y(Me)(tmeda)]. The bonding features of the newly synthesized complexes are analyzed by single-crystal X-ray diffraction (SCXRD) and heteronuclear (Y-89, P-31) NMR spectroscopy.

Automated summary

This article reports the synthesis of a novel yttrium gallabenzene complex from Y(GaMe4)(3) and K(2,4-dtbp) through a tandem salt metathesis/methane elimination reaction, as well as the reactivity of this complex with various Lewis bases.