Process for preparing addition polymerization catalysts via metal center oxidation

Claim 1

A process for the preparation of a catalyst useful for addition polymerizations corresponding to the formula: L.sub.l MX.sub.n.sup.+ A.sup.-, wherein: L independently each occurrence is an anionic or nonanionic ligand or ligand system; M is a metal of group 4-8 of the periodic table also having an oxidation state, M*, one less than the state of the metal in the catalyst; X independently each occurrence is hydride; halide; or a group selected from alkyl, alkenyl, silyl, germyl, aryl, and combinations thereof having up to 20 carbon, silicon or germanium atoms, and oxygen, nitrogen, phosphorus or sulfur containing derivatives thereof; l is an integer greater than or equal to 1; n is an integer greater than or equal to 1, and the sum of l and n together is one less than the valence of M; and A - is a monovalent compatible noncoordinating anion, the steps of the process comprising contacting in a noninterfering, noncoordinating solvent at a temperature from -100° C. to 300° C. a reduced metal derivative corresponding to the formula: L l M*X n , wherein L, l, n, X, and M* are as previously defined with an oxidizing agent capable of oxidizing M* to M and which in reduced form is noninterfering with the resulting catalyst, said oxidizing agent comprising a cationic oxidizer and a compatible noncoordinating anion, A - .