Catalysts for the polymerization of unsaturated compounds
View Patent ↗Bisimine compounds of the formula (I) where the symbols have the following meanings: A is a nonmetal selected from among N, S, O and P, R 1 is a radical of the formula NR 5 R 6 , R 2 is a radical of the formula NR 5 R 6 or NR 7 R 8 , alkyl, aryl or cycloalkyl, R 5 and R 6 together with the N atom form a 5-, 6- or 7-membered ring in which one or more of the —CH— or —CH 2 — groups may be replaced by suitable heteroatom groups and which may be saturated or unsaturated and unsubstituted or substituted or be fused with further carbacyclic or heterocarbacyclic 5- or 6-membered rings which may in turn be saturated or unsaturated and substituted or unsubstituted, and R 7 and R 8 are, independently of one another, alkyl, aryl or cycloalkyl radicals, and R 3 , R 4 are, independently of one another, H or alkyl, aryl or cycloalkyl radicals, and n is 1 or 2, are used to prepare bisimidinato complexes which can be used in the polymerization of unsaturated compounds.
1. A compound of the formula (VI),
where the symbols have the following meanings;
A is a nonmetal selected from among N, S, O and P,
R 1 is a radical of the formula NR 5 R 6 ,
R 2 is a radical of the formula NR 5 R 6 or NR 7 R 8 , alkyl, aryl or cycloalkyl,
R 5 and R 6 together with the N atom form a 5-, 6- or 7-membered ring in which one or more of the —CH— or —CH 2 — groups may be replaced by suitable heteroatom groups and which may be saturated or unsaturated and unsubstituted or substituted or be fused with further carbacyclic or heterocarbacyclic 5- or 6-membered rings which may in turn be saturated or unsaturated and substituted or unsubstituted, and
R 7 and R 8 are, independently of one another, alkyl, aryl or cycloalkyl radicals, and
R 3 , R 4 are, independently of one another, H or alkyl, aryl or cycloalkyl radicals,
n is 1 or 2,
M is a transition metal of groups 7, 8, 9 or 10 of the Periodic Table of the Elements, and
X is a halide or a C 1 -C 6 -alkyl radical and
m is the valence of the metal.
2. A compound as claimed in claim 1 , wherein M=Fe or Co and m=2.
3. A process for preparing compounds of the formula (VI) of claim 1 by reacting corresponding compounds of the formula (I)
in which R 1 to R 4 , A and n are as defined for formula (VI). with salts of transition metals of groups 7, 8, 9 or 10 of the Periodic Table of the Elements.
4. A process for preparing polyolef ins by polymerization of unsaturated compounds in the presence of an activator and a compound of the formula (VI) as claimed in claim 1 as catalyst.
5. A process as claimed in claim 4 , wherein the catalyst is present in the polymerization either as a homogeneous solution or in heterogeneous form immobilized on a support.
6. A process as claimed in claim 4 , wherein metbylaluminoxane or N,N-dimethylanilinium tetrakis (pentafluoro-phenyl) borate is used as activator.
7. A process as claimed in claim 4 , wherein an unsaturated compound or a combination of unsaturated compounds selected from among ethylene, C 3 -C 20 -monoolefins and cycloolefins is used.