| abstract |
Effective catalyst in the selective hydrogenation ofnolefinic double bonds, comprising the reaction productnbetween:n (A) at least one cyclopentadienyl complex of a transitionnmetal having the following general formulan(I):n (R)M(R 1 )(R 2 )(R 3 ) n wherein: M is selected from titanium, zirconiumnand hafnium, preferably titanium; nR is an anion containing an η 5 -cyclopentadienylnring co-ordinated to M; and neach R 1 , R 2 or R 3 , independently, representsnan organic or inorganic group ofnan anionic nature bound to M, and may,nparticularly, be hydride, halide, anC 1 -C 8 alkyl group, a C 3 -C 12 alkylsilylngroup, a C 5 -C 8 cycloalkyl group, a C 6 -C 10 naryl group, a C 1 -C 8 alkoxyl group, anC 1 -C 8 carboxyl group, a C 2 -C 10 dialkylamidengroup and a C 4 -C 20 alkylsilylamidengroup; nthe above compound (I) being solid, supported orndispersed in an inert liquid medium; and (B) at least one organometallic compound of magnesiumnhaving the following formula (II):n Mg(R 4 ) n (R 5 ) (2-n) n wherein: R 4 is an aliphatic or aromatic hydrocarbonngroup having from 1 to 20 carbonnatoms, nR 5 is halogen or a group such as R 4 , and n"n" is a decimal number between 0.5 andn2.0, preferably 2. |