Organometallic complex having the formula (IAP)M(X).sub.n which can be used
for die formation of catalytic systems wherein: M is a metal selected from
transition metals and lanthanides, in oxidation state "s" positive and
different from zero; each X is independently a group of an anionic nature
bound to the metal as an anion in an ionic couple or with a convalent bond
of the ".sigma." type; "n" expresses the number of X groups sufficient for
neutralizing the formal "+s" charge of the metal M, and (IAP) represents a
neutral bond consisting of a mono-imine of 2,6-diacylpyridine. Said
complex is prepared with relatively simple methods and can be used,
combined with a suitable co-catalyst, such as for example, an aluminoxane,
as a catalyst in normal (co)polymerization processes of .alpha.-olefins,
and especially ethylene.
