Ruthenium-based metathesis catalysts, precursors for their preparation and their use

Patent metadata

Field	Value
Publication number	US-11241680-B2
Application number	US-201816014615-A
Country	US
Kind code	B2
Filing date	Jun 21, 2018
Priority date	Oct 29, 2012
Publication date	Feb 8, 2022
Grant date	Feb 8, 2022

Abstract

The invention is directed to ruthenium-based metathesis catalysts of the Grubbs-Hoveyda type. The new 2-aryloxy-substituted ruthenium catalysts described herein reveal rapid initiation behavior. Further, the corresponding styrene-based precursor compounds are disclosed. The catalysts are prepared in a cross-metathesis reaction starting from styrene-based precursors which can be prepared in a cost-effective manner.
The new Grubbs-Hoveyda type catalysts are suitable to catalyze ring-closing metathesis (RCM), cross metathesis (CM) and ring-opening metathesis polymerization (ROMP). Low catalyst loadings are necessary to convert a wide range of substrates including more complex and critical substrates via metathesis reactions at low to moderate temperatures in high yields within short reaction times.

First claim

The invention claimed is:

1. A compound of formula (I) for the preparation of ruthenium-based catalysts

wherein
a, b, c and d are, independently from each other, selected from hydrogen, straight chain or branched alkyl groups including C 1 -C 10 -alkyl, C 1 -C 10 -alkoxy, C 1 -C 10 -alkylthio, C 1 -C 10 -silyloxy, C 1 -C 10 -alkylamino, optionally substituted C 6 -C 14 -aryl, optionally substituted C 6 -C 14 -aryloxy, optionally substituted C 6 -C 14 -heteroaryl;
R 1 is hydrogen, straight chain or branched C 1 -C 10 -alkylthio, C 1 -C 10 -silyloxy, C 1 -C 10 -alkylamino, C 1 -C 10 -dialkylamino, or electron-withdrawing groups (EWG) selected from the group consisting of trifluormethyl (—CF 3 ), nitro (—NO 2 ), formyl (—CHO), C 1 -C 10 -carboxyl, C 1 -C 10 -alkylamido, C 1 -C 10 -aminocarbonyl, nitrile (—CN) or C 1 -C 10 -sulfonamide;
R 2 is hydrogen, straight chain or branched C 1 -C 10 -alkyl groups.

2. The compound according to claim 1 , wherein
a, b, c and d each are hydrogen;
R 1 is dimethylamino (NMe 2 -), nitro (NO 2 —); and
R 2 is hydrogen, methyl, ethyl, n-propyl, iso-propyl, n-butyl or iso-butyl.

3. The compound according to claim 2 , having the formula (Ia)

4. A method for preparing the catalyst according to claim 1 , comprising reacting a compound of formula (I)

wherein
a, b, c and d are, independently from each other, selected from hydrogen, straight chain or branched alkyl groups including C 1 -C 10 -alkyl, C 1 -C 10 -alkoxy, C 1 -C 10 -alkylthio, C 1 -C 10 -silyloxy, C 1 -C 10 -alkylamino, optionally substituted C 6 -C 14 -aryl, optionally substituted C 6 -C 14 -aryloxy, optionally substituted C 6 -C 14 -heteroaryl;
R 1 is straight chain or branched C 1 -C 10 -alkylthio, C 1 -C 10 -silyloxy, C 1 -C 10 -alkylamino, C 1 -C 10 -dialkylamino, or electron-withdrawing groups (EWG) selected from the group consisting of trifluormethyl (—CF 3 ), nitro (—NO 2 ), formyl (—CHO), C 1 -C 10 -carboxyl, C 1 -C 10 -alkylamido, C 1 -C 10 -aminocarbonyl, nitrile (—CN) or C 1 -C 10 -sulfonamide:
R 2 is hydrogen, straight chain or branched C 1 -C 10 -alkyl groups

with a Ru-starting compound having the formula (V):

in a cross metathesis reaction,
wherein
L is a phosphine ligand selected from the group of tri-iso-propyl-phosphine, tricyclohexylphosphine (PCy 3 ), tricyclopentylphosphine, cyclohexylphobane, 2,2,4-trimethylpentylphobane or isobutyl-phobane or a NHC ligand selected from the group of 1,3-bis-(2,4,6-trimethylphenyl)-imidazolidine-2-ylidene (“SIMes”), 1,3-bis-(2,6-di-isopropylphenyl)-imidazolidine-2-ylidene (“SIPr”) or 1,3-bis-(2,6-diisopropylphenyl)-imidazoline-2-ylidene (“IPr”) and
L′ is a leaving ligand from the group of tri-iso-propylphosphine, tricyclohexylphosphine (PCy 3 ), tricyclopentylphosphine, cyclo-hexylphobane, 2,2,4-trimethylpentyl-phobane, isobutylphobane or substituted or unsubstituted pyridine ligands;
X is an anionic ligand selected from the group of halogen anions (Cl − , Br − , I − ).

5. The method for preparing the catalysts according to claim 4 , wherein
L is a NHC ligand selected from the group of 1,3-bis-(2,4,6-trimethylphenyl)imidazolidine-2-ylidene (“SIMes”), 1,3-bis-(2,6-di-isopropylphenyl)-imidazolidine-2-ylidene (“SIPr”) or 1,3-bis-(2,6-di-isopropylphenyl)-imidazoline-2-ylidene (“IPr”),
L′ is pyridine,
X is Cl − .

Assignees

• Umicore Ag & Co Kg

Inventors

• Plenio Herbert
• Kos Pavlo
• Savka Roman

Classifications

• B01J31/2278 Primary

  Complexes comprising two carbene ligands differing from each other, e.g. Grubbs second generation catalysts · CPC title

• B01J31/2273

  with only nitrogen as heteroatomic ring members, e.g. 1,3-diarylimidazoline-2-ylidenes · CPC title

• B01J2531/821

  Ruthenium · CPC title

• C07F15/0046

  Ruthenium compounds · CPC title

• B01J2231/324

  Cyclisations via conversion of C-C multiple to single or less multiple bonds, e.g. cycloadditions · CPC title