Abstract
Proton exchange reaction of isolated or in situ prepared heterobimetallic peralkylated Sm complexes with sterically demanding mono- and bisphenols led to the formation of aluminum alkyl samarium-aryl oxide adducts in good yields. Divalent complexes formulated as Sm[(mu-2,6-bis (phenylphenoxy))](2)[(mu-Me)(AlMe2)](2) (1), (Sm{mu-eta(6')-[6,6'-methylene-bis(2-tert-butyl-4-methylphenoxy)][AlMe2]} {mu-Me)(2){AlMel)(mu-Me) (3), {Sm-mu-[6,6'-methylenebis(2-tert-butyl-4-methylphenol)][mu-Me2AlMe2]}(2) (6), and Sm-{mu-[6,6'-methylenebis(2-tert-butyl-4-methylphenol)]}(2)-mu-AlMe2]}(2) (7) were isolated and characterized including via solid structure determination. The reactivity of these compounds toward both oxidation and insertion into the [Sm-Me-Al] fragment was probed with both CO2 and tert-butylisocyanate, affording Sm{[(mu-2,6-bis(phenylphenoxy))(2)AlMe2]-[mu-(acetato)-(2,6-bis(phenylphenoxy))AlMe2][1,2-dimethoxyethane]){C6H14)(0.25) (2) and Sm{mu-[6,6'-methylenebis (2-tert-butyl-4-methylphenol)]-mu-[N-tert-butylacetamidate]AlMe2{C7H8}(1.5) (4), respectively. The trivalent 6 exhibited significant activity as a catalyst for ethylene polymerization without the need for further activation and which may be regarded as an example of a single-component lanthanide ethylene polymerization catalyst without a cyclopentadienyl ligand.