Cationic η3-allyl sulfide complexes of nickel(II) for the polymerization of butadiene in aqueous emulsion

Reaction of the dimeric allyl-nickel(II) chloro complex [Ni(η3-C3H5)(μ-Cl)]2 (5) with sulfur donor ligands (L = L10–L13) in the presence of View the MathML sourceNaBAr4F (View the MathML sourceAr4F = 3,5-(CF3)2C6H3) gives the corresponding cationic mononuclear complexes of the type [Ni(η3-C3H5)(L)2]+ (1–4) [L = L10 = diphenyl sulfide (1); L = L11 = 4,4′-thiodiphenol (2); L = L12 = 4,4′-thio-bis(6-tert -butyl-o -cresol) (3); L = L13 = 4,4′-thio-bis (6-tert -butyl-m -cresol) (4)]. All of these complexes were characterized by elemental analysis and NMR spectroscopy, as well as the representative complex 3 additionally by single-crystal X-ray analysis. In comparison to the known complex [Ni(η3-C3H5)(η6-BHT)][BView the MathML sourceAr4F] (BHT = 3,5-di-tert-butyl-4-hydroxytoluene), the herein described cationic complexes show an increased stability towards water. The activity of the complexes for butadiene polymerization in aqueous emulsions was studied.