Single-carbon bridges bys cyclopentadienyl compounds and...

Details Single-carbon bridges bys cyclopentadienyl compounds and... Single-carbon bridges bys cyclopentadienyl compounds and...

1999-10-26

2003-03-18

Shaver, Paul F. (Department: 1621)

Organic compounds -- part of the class 532-570 series

Organic compounds

Heavy metal containing

C556S009000, C556S011000, C556S012000, C556S027000, C556S052000, C556S053000, C556S112000, C556S113000, C556S413000, C556S402000, C556S428000, C556S489000, C585S026000, C585S027000

Reexamination Certificate

active

06534665

ABSTRACT:

The present inventions relates to a new process for synthesizing single carbon bridge bis cyclopentadienyl compounds and metal complexes obtained therefrom. And to the use of these complexes for polymerization and copolymerization of olefins.
The metallocene compounds field has experimented a big development since the first syntheses of these compounds in the fifties (G. Wilkinson et al.,
J. Am. Chem. Soc.,
(1953), 75, 1011). This development is basically due to the large increase in the number of applications wherein these compounds are used. So, they can be used as catalysts of hydrogenation, epoxidation, double bond isomerization, ketones reduction, aldolic reaction, synthesis of different substituted olefins, etc., but their largest use is as catalyst components for olefin polymerization, as they can be activated for this use by alumoxanes or other non-coordinative anion precursors (for example boron compounds). In this field metallocenes of group 4 (Ti, Zr, Hf, in particular have been developed, but also metallocenes of groups 3, 5 and 6. Metallocenes have been prepared for working in very different conditions (solution, suspension, mass, gas phase, high pressure and temperature processes, etc.). They have been used for polymerizing and copolymerizing simple I-olefins, basically ethylene and propylene, but also more complex olefins (cyclolefins, diolefins and also olefins with polar groups (see for example W. A. Nugent et al.,
J. Am. Chem. Soc.
(1989), 111, 6435; R. M. Waymouth et al.,
J. Am. Chem. Soc.
(1992), 114, 9679; H. Yasuda et al.,
Macromol. Chem. Phys,
(1995), 196,2417).
For adapting to the different needs of each application, very different metallocenes were synthesized, basically differing by the different substitutions on the cyclopentadienyl rings of the complex, as it is possible to influence in this way, both sterically and electronically, the reactivity of the active center. A specially relevant development was the introduction of at least one bridge connecting the two cyclopentadienyl rings (H. H Britzinger et al.,
J. Organomet. Chem.,
(1979), 173, 6270), since it determines the reactivity of the metallocene conditioning its steric nature in two ways: (1) influencing the monomer greater or smaller accessibility to the active center as the bridge largerly determines the angle spread between the cyclopentadienyl rings and (2) preventing the free rotation of the rings and, therefore, determining the symmetry of the whole molecule. On the other hand the bridge can also influence the electronic nature of the metallocene. In this way it has been obtained a better stability of certain metallocenes, a greater or smaller discrimination of the monomers that are incorporated into the polymer because of their size and the possibility of obtaining stereoregular I-olefin polymers (isotactic, syndiotactic, hemiiostactic).
It is known hat in order to obtain specific polymer structures, the use of a single-carbon bridge is preferred (e.g. EP A 351 392). A common process for obtaining this type of bridged ligands comprises reacting a ketone with a cyclopentadienyl in the presence of a strong base, then the obtained fulvene is reacted with another cyclopentadienyl compound again in the presence of a base. Generally these procedure requires a purification of the fulvene or optionally the use of a commercially available one.
Particularly for industrial uses, a one-step process is preferred to a two-step process. A one-step process is developed, for example, in EP 751 143, wherein one or two cyclopentadienyl compounds, at least one being a substituted cyclopentadienyl are reacted with a carbonyl compound in the presence of a base and a phase transfer catalyst; the preferred bases are hydroxides of elements belonging to groups 1, 2 or 13 of the periodic table; in the examples sodium hydroxide is used. Another one-step process is described in EP 722 949. It relates to a process for preparing bis-cyclopentadienyl compounds bridged by a single carbon atom. The compound is prepared by reacting a carbonyl compound with a cyclopentadienyl compound in the presence of a base and of an oxygen-containing solvent having an atomic ratio carbon/oxygen not higher than 3.
These one-step processes make use of strong bases such as sodium or potassium hydroxide; therefore they are not adequate for synthesizing bridged bis cyclopentadienyl compounds wherein the bridge is functionalized with hydrolizable groups. On the other hand, bridged bis cyclopentadienyl compounds having these groups, such as for example trialkyl sililoxy group, bonded to the bridge can be useful to obtain complexes that can be, for example, easily supported on a heterogeneous carrier (see for example EP 839 836). Therefore it could be desirable a new process that permits an easy and one-step synthesis of this kind of compounds.
An object of the present invention is a new process for synthesizing single-carbon bridged bis cyclopentadienyl compounds wherein the bridge contains a hydrolizable group.
A further object of the present invention is a new class of single-carbon bridged bis cyclopentadienyl compounds substituted on the bridge with a hydrolizable group, and the metallocene obtained by the use of these ligands.
Another further object of the present invention is a new class of single carbon bridged metallocenes obtained by hydrolisis of the functional group on the bridge.
Another still further object of the present invention is the use of the previosly described metallocenes for polymerization and copolymerization of olefins.
The present invention relates to bis cyclopentadienyl compounds, wherein the two cyclopentadienyl rings are connected to each other by a single carbon atom characterized by the following general formula I
wherein
each L, equal to or different from each other, is selected from the group consisting of:
 wherein
each R
1
equal to or different from each other is selected from the group consisting of hydrogen, a monovalent aliphatic or aromatic hydrocarbon group, optionally containing heteroatoms of group 14 to 16 of the periodic table of the elements and boron; optionally two R
1
form an aromatic or aliphatic ring; preferably R
1
is selected from the group consisting of: hydrogen, C
1
-C
20
alkyl; C
3
-C
20
cycloalkyl; C
6
-C
20
aryl; C
2
-C
20
alkenyl; C
7
-C
20
arylalkyl; C
7
-C
20
alkylaryl; C
3
-C
20
arylalkenyl; CH
8
-C
20
alkenylaryl, linear or branched, optionally substituted by BR
2
, OR, SiR
3
, NR
2
;
wherein each R is independently selected from the group consisting of C
1
-C
20
alkyl, C
3
-C
20
cycloalkyl, C
6
-C
20
aryl, C
2
-C
20
akenyl, C
7
-C
20
arylalalkyl, C
7
-C
20
alkaryl, C
8
-C
20
arylalkenyl, C
8
-C
20
alkenylaryl linear or branched; two or more R can also form an aliphatic or aromatic ring; preferably R is selected from the group consisting of: butyl, propyl, ethyl, methyl;
each R
2
, equal to or different from each other, is selected from the group consisting of: C
1
-C
20
alkylidene, C
3
-C
20
cycloalkylidene, C
2
-C
20
alkenylidene, C
6
-C
20
arylidene, C
7
-C
20
alkylarylidene, C
7
-C
20
arylalkylidene, C
8
-C
20
arylalkenylidene, C
8
-C
20
alkenylarylidene, linear or branched, optionally containing heteroatoms of group 14 to 16 of the periodic table of the elements or boron; one R
2
is optionally absent; in this case A is directly bonded to C and is preferably hydrogen; preferably R
2
is selected from the group comprising: butylidene, propylidene, ethylidene, methylidene;
each A, equal to or different from each other, is selected from the group consisting of: hydrogen, OR
3
, NRR
4
, or SR
5
wherein
each R
3
is independently selected from the group consisting of: R, SiR
3
, SO
2
R, CR
2
OR; CR
2
SR, or any other group used as protective group of alcohols in organic synthesis;
each R
4
is independently selected from the group consisting of: R, SiR
3
, SO
2
R, or any other group used as protective group of amines in organic synthesis;
each R
5
is independently selected from the group consisting of: R, SiR
3
, CR
2
OR; CR
2
SR,

Affiliated with

Also associated with

Rating

Single-carbon bridges bys cyclopentadienyl compounds and... does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Single-carbon bridges bys cyclopentadienyl compounds and..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Single-carbon bridges bys cyclopentadienyl compounds and... will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-3025017