Process for preparing 1 3-disubstituted cyclopentadienyl ligands and transition metal complexes thereof
AssigneeWitco Corporation
InventorRichard Lisowsky
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Abstract
The invention relates to an improved process which, starting from 2-cyclopenten-1-ones substituted in the 3-position, gives a high yields of 1,3-dialkylcyclopentadienes which can be directly metallated and reacted to give the corresponding 1,3-dialkylcyclopentadienyl-transition metal complexes.
Claims11
A process for preparing a 1,3-disubstituted cyclopentadienyl-transition metal complex, comprising in a first step, reacting a cyclopent-2-en-1-one substituted in the 3-position with a Grignard compound of the formula R.sup.2 MgX according to equation (A) ##STR7## and hydrolyzing and dehydrating the alkoxide formed in equation (A) with not more than a stoichiometric amount of water, according to equation (B) ##STR8## wherein each of R.sup.2 and R.sup.3 is independently of one another selected from the group consisting of C.sub.1 -C.sub.20 substituted and unsubstituted alkyl, alkenyl, cycloalkyl, aryl, and arylalkyl radicals;
- and X is Cl, Br or I;
- and, in a second step, directly metallating the cyclopentadienyl product formed in equation (B), according to equation (C) ##STR9## wherein M' is metallating agent;
- M.sup.1 is Sc, Ti, Zr, Hf, Fe, V or Cr;
- X.sup.1 is Cl, Br or I;
- m is the oxidation state of M.sup.1 ;
- and
- n.ltoreq.m;
- and reacting the product (C-1) formed in equation (C) to form the corresponding complex of said product and said transition metal halide.
A process for preparing a 1,3-disubstituted cyclopentadienyl compound, comprising reacting a cyclopent-2-en-1-one substituted in the 3-position with a Grignard compound of the formula R.sup.2 MgX according to equation (A) ##STR10## and hydrolyzing and dehydrating the alkoxide formed in equation (A) with not more than a stoichiometric amount of water, according to equation (B) ##STR11## wherein each of R.sup.2 and R.sup.3 independently of one another is selected from the group consisting of C.sub.1 -C.sub.20 substituted and unsubstituted alkyl, alkenyl, cycloalkyl, aryl, and arylalkyl radicals;
- and X is Cl, Br or I.
Dependencies are inferred from the claim text.