# US 12,595,321 B2 · Catalyst system based on a rare-earth metallocene and a co-catalyst having a plurality of carbon-magnesium bonds

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- Number: US 12,595,321 B2
- Document ID: US12595321B2
- Status: Granted
- Kind: B2
- Application number: 18/038,505
- Filed: 2021-11-19
- Published: 2024-04-11
- Granted: 2026-04-07
- Earliest claimed: 2020-11-24
- Assignees: Compagnie Generale Des Etablissements Michelin; Centre National De La Recherche Scientifique; Ecole Superieure De Chimie Physique Electronique De Lyon; Universite Claude Bernard Lyon 1
- Applicants: Compagnie Generale Des Etablissements Michelin; Centre National De La Recherche Scientifique; Ecole Superieure De Chimie Physique Electronique De Lyon; Université Claude Bernard Lyon 1
- Inventors: Robert Ngo; Nicolas Baulu; Christophe Boisson; Franck D'Agosto; François Jean-Baptiste-Dit-Dominique; Julien Thuilliez
- Web page: https://patentgrep.com/patent/US12595321B2

## CPC

- C08F 10/02: Ethene
- C08F 8/04: Reduction, e.g. hydrogenation
- C08F 8/20: Halogenation
- C08F: MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS

## Abstract

A catalytic system based on at least one rare-earth metallocene and an organomagnesium reagent as co-catalyst of formula RB—(Mg—RA)m—Mg—RB is provided. According to the formula, RB comprises a benzene nucleus substituted with the magnesium atom. One of the carbon atoms of the benzene nucleus ortho to the magnesium is substituted with a methyl, an ethyl or an isopropyl or forms a ring with the carbon atom which is its closest neighbour and which is meta to the magnesium. The other carbon atom of the benzene nucleus ortho to the magnesium is substituted with a methyl, an ethyl or an isopropyl. RA is a divalent aliphatic hydrocarbon-based chain, optionally interrupted with one or more oxygen or sulfur atoms or with one or more arylene groups. The m is a number greater than or equal to 1, preferably 1. The catalytic system allows the synthesis of dienic and/or ethylenic telechelic polymers.

## Claims

### Claim 1

A catalytic system based at least:
on a metallocene of formula (Ia) or (Ib),
on an organomagnesium reagent as co-catalyst,
{P(Cp1)(Cp2)Y} (Ia)
Cp3Cp4Y (Ib)
Y denoting a group including a rare-earth metal atom,
Cp1, Cp2, Cp3 and Cp4, which are identical or different, being chosen from the group consisting of fluorenyl groups, cyclopentadienyl groups and indenyl groups, the groups being substituted or unsubstituted,
P being a group bridging the two groups Cp1 and Cp2 and comprising a silicon or carbon atom, the organomagnesium reagent being a compound of formula (II)
RB—(Mg—RA)m—Mg—RB (II)
RB being different from RA,
RB comprising a benzene nucleus substituted with the magnesium atom, one of the carbon atoms of the benzene nucleus ortho to the magnesium being substituted with a methyl, an ethyl, an isopropyl or forming a ring with the carbon atom which is its closest neighbour and which is meta to the magnesium, the other carbon atom of the benzene nucleus ortho to the magnesium being substituted with a methyl, an ethyl or an isopropyl,
RA being a divalent aliphatic hydrocarbon-based chain, interrupted or not with one or more oxygen or sulfur atoms or with one or more arylene groups,
m being a number greater than or equal to 1.

### Claim 2 (depends on 1)

The catalytic system according to claim 1, in which Cp1 and Cp2 are identical and are chosen from the group consisting of substituted fluorenyl groups and the unsubstituted fluorenyl group of formula C13H8.

### Claim 3 (depends on 1)

The catalytic system according to claim 1, in which the symbol Y represents the group Met-G, with Met denoting the rare-earth metal atom and G denoting a group comprising the borohydride BH4 unit or denoting a halogen atom chosen from the group consisting of chlorine, fluorine, bromine and iodine.

### Claim 4 (depends on 3)

The catalytic system according to claim 3, in which G denotes a chlorine atom or the group of formula (III)
(BH4)(1+y)-Ly-Nx (III)
in which
L represents an alkali metal chosen from the group consisting of lithium, sodium and potassium,
N represents a molecule of an ether,
x, which may or may not be an integer, is greater than or equal to 0,
y, which is an integer, is greater than or equal to 0.

### Claim 5 (depends on 1)

The catalytic system according to claim 1, in which the rare-earth metal is a lanthanide, the atomic number of which ranges from 57 to 71.

### Claim 6 (depends on 1)

The catalytic system according to claim 1, in which the bridge P corresponds to the formula ZR1R2, Z representing a silicon or carbon atom and R1 and R2, which are identical or different, each representing an alkyl group comprising from 1 to 20 carbon atoms.

### Claim 7 (depends on 1)

The catalytic system according to claim 1, in which the metallocene is of formula (III-1), (III-2), (III-3), (III-4) or (III-5):
[Me2Si(Flu)2Nd(μ-BH4)2Li(THF)] (III-1)
[{Me2SiFlu2Nd(μ-BH4)2Li(THF)}2] (III-2)
[Me2SiFlu2Nd(μ-BH4)(THF)] (III-3)
[{Me2SiFlu2Nd(μ-BH4)(THF)}2] (III-4)
[Me2SiFlu2Nd(μ-BH4)] (III-5)
Flu representing the C13H8 group.

### Claim 8 (depends on 1)

The catalytic system according to claim 1, in which, if one of the two carbon atoms of the benzene nucleus of RB ortho to the magnesium is substituted with an isopropyl, the second carbon atom of the benzene nucleus of RB ortho to the magnesium is not substituted with an isopropyl.

### Claim 9 (depends on 1)

The catalytic system according to claim 1, in which the carbon atoms of the benzene nucleus of RB ortho to the magnesium are substituted with a methyl or an ethyl.

### Claim 10 (depends on 1)

The catalytic system according to claim 1, in which the organomagnesium reagent is of formula (IV-m)
R1 and R5, which are identical or different, represent a methyl or an ethyl,
R2, R3 and R4, which are identical or different, being a hydrogen atom or an alkyl,
RA being a divalent aliphatic hydrocarbon-based chain, interrupted or not with one or more oxygen or sulfur atoms or with one or more arylene groups,
m being a number greater than or equal to 1.

### Claim 11 (depends on 1)

The catalytic system according to claim 1, in which RA is a branched or linear alkanediyl, cycloalkanediyl or xylenediyl radical.

### Claim 12 (depends on 1)

A process for preparing a first telechelic polymer, which comprises a step of polymerizing a monomer M in the presence of a catalytic system defined in claim 1, the monomer M being chosen from the group of monomers consisting of 1,3-dienes, ethylene, α-monoolefins and mixtures thereof.

### Claim 13 (depends on 1)

A process for preparing a second telechelic polymer, which comprises a step of polymerizing a monomer M in the presence of a catalytic system defined in claim 1, this polymerization step being followed by a step of functionalization with a modifying agent, the monomer M being chosen from the group of monomers consisting of 1,3-dienes, ethylene, α-monoolefins and mixtures thereof.

### Claim 14 (depends on 1)

A process for preparing a polymer, which comprises a step of polymerizing a monomer M in the presence of a catalytic system defined in claim 1 and a termination reaction with a protic compound, the monomer M being chosen from the group of monomers consisting of 1,3-dienes, ethylene, α-monoolefins and mixtures thereof.

### Claim 15 (depends on 1)

A telechelic polymer of formula (V)
RB—Mg-poly-RA-poly-Mg—RB (V)
RA and RB being defined according to claim 1,
the name “poly” denoting a polymer chain of a 1,3-diene, of ethylene or of an α-monoolefin, or mixtures thereof.

### Claim 16 (depends on 1)

The catalytic system according to claim 1, in which m is equal to 1.

### Claim 17 (depends on 2)

The catalytic system according to claim 2, in which Cp1 and Cp2 each represent an unsubstituted fluorenyl group of formula C13H8.

### Claim 18 (depends on 4)

The catalytic system according to claim 4, in which N represents a molecule of diethyl ether or tetrahydrofuran.

### Claim 19 (depends on 5)

The catalytic system according to claim 5, in which the rare-earth metal is neodymium.

### Claim 20 (depends on 6)

The catalytic system according to claim 6, in which R1 and R2 each represent a methyl.