| abstract |
Effective catalyst in the selective hydrogenation of olefinic double bonds, comprising the reaction product between:(A) at least one cyclopentadienyl complex of a transition metal having the following general formula (I): wherein:M is selected from titanium, zirconium and hafnium, preferably titanium;R is an anion containing an eta5-cyclopentadienyl ring co-ordinated to M; andeach R1, R2 or R3, independently, represents an organic or inorganic group of an anionic nature bound to M, and may, particularly, be hydride, halide, a C1-C8 alkyl group, a C3-C12 alkylsilyl group, a C5-C8 cycloalkyl group, a C6-C10 aryl group, a C1-C8 alkoxyl group, a C1-C8 carboxyl group, a C2-C10 dialkylamide group and a C4-C20 alkylsilylamide group; the above compound (I) being solid, supported or dispersed in an inert liquid medium; and(B) at least one organometallic compound of magnesium having the following formula (II): wherein:R4 is an aliphatic or aromatic hydrocarbon group having from 1 to 20 carbon atoms,R5 is halogen or a group such as R4, and"n" is a decimal number between 0.5 and 2.0, preferably 2. |