Backfunctionalized imidazolinium salts and NHC carbene-metal complexes

Patent metadata

Field	Value
Publication number	US-10214494-B2
Application number	US-201715725848-A
Country	US
Kind code	B2
Filing date	Oct 5, 2017
Priority date	Oct 9, 2014
Publication date	Feb 26, 2019
Grant date	Feb 26, 2019

Abstract

Backfunctionalized imidazolinium salts and methods of synthesizing the same and NHC carbene-metal complexes therefrom. For backfunctionalized imidazolinium salts of the formula:

Wherein R 1 is selected from the group consisting of an ester group, an amide group, and an aromatic group; R 2 is selected from the group consisting of hydrogen, an ester group, an amide group, and an aromatic group; R 3 and R 4 are each an aliphatic group; and
X is an anion; the method comprises cyclization of a halogenated acrylate with Hünig's base in a solvent.

First claim

What is claimed is:

1. An N-heterocyclic carbene-metal complex comprising:
a metal; and
a first ligand coordinated to the metal and comprising a free N-heterocyclic carbene synthesized from a backfunctionalized imidazolinium salt comprising the formula:

R 1 being selected from the group consisting of an ester group, an amide group, and an aromatic group;
R 2 being selected from the group consisting of hydrogen, an ester group, an amide group, and an aromatic group;
each of R 3 and R 4 being separately selected from the group consisting of a C 1 -C 20 alkyl group, C 1 -C 20 partially fluorinated alkyl group, an aryl group, an aryl group with para CF 3 functionality, an aryl group having C 1 -C 20 partially fluorinated alkyl groups or partially fluorinated alkoxy groups, and a C 1 -C 20 partially fluorinated aliphatic group, and a C 1 -C 20 aryl group; and
X is an anion.

2. The N-heterocyclic carbene-metal complex of claim 1 , wherein the metal is selected from the group consisting of rhenium, ruthenium, osmium, rhodium, iridium, palladium, platinum, silver, and gold.

3. The N-heterocyclic carbene-metal complex of claim 1 , further comprising:
a second ligand coordinated to the metal, the second ligand comprising another free N-heterocyclic carbene synthesized from a backfunctionalized imidazolinium salt comprising the formula:

R 1 being selected from the group consisting of an ester group, an amide group, and an aromatic group;
R 2 being selected from the group consisting of hydrogen, an ester group, an amide group, and an aromatic group;
each of R 3 and R 4 being separately selected from the group consisting of a C 1 -C 20 alkyl group, C 1 -C 20 partially fluorinated alkyl group, an aryl group, an aryl group with para CF 3 functionality, an aryl group having C 1 -C 20 partially fluorinated alkyl groups or partially fluorinated alkoxy groups, and a C 1 -C 20 partially fluorinated aliphatic group, and a C 1 -C 20 aryl group; and
X is an anion.

4. The N-heterocyclic carbene-metal complex of claim 3 , further comprising:
a third ligand selected from the group consisting of an acetylacetonate, alkoxy, alkyl, aryl, aryloxy, carbonyl, halide, imido, oxo, pyridine, trialkylphosphine, and triarylphosphine, the third ligand being coordinated to the metal.

5. The N-heterocyclic carbene-metal complex of claim 1 , further comprising:
a second ligand selected from the group consisting of an acetylacetonate, alkoxy, alkyl, aryl, aryloxy, carbonyl, halide, imido, oxo, pyridine, trialkylphosphine, and triarylphosphine, the second ligand being coordinated to the metal.

6. The free N-heterocyclic carbene of claim 2 , wherein X is a halogen anion.

7. The free N-heterocyclic carbene of claim 2 , wherein R 1 is in a trans-configuration with respect to R 2 .

8. The N-heterocyclic carbene-metal complex of claim 1 , wherein the free N-heterocyclic carbene is synthesized by deprotonation.

9. The N-heterocyclic carbene-metal complex of claim 8 , wherein deprotonation includes reacting the backfunctionalized imidazolinium salt with silver oxide.

10. The N-heterocyclic carbene-metal complex of claim 1 , wherein the free N-heterocyclic carbene is synthesized by formamidine cyclization of a halogenated acrylate with a primary base in a solve, the primary base being Hünig's base.

11. The N-heterocyclic carbene-metal complex of claim 10 , wherein the solvent is acetone and toluene.

Assignees

• Us Air Force

Inventors

• Blanski Rusty L
• Grubbs Robert H

Classifications

• C07F15/0046

  Ruthenium compounds · CPC title

• C07F15/0033

  Iridium compounds · CPC title

• C07D233/28 Primary

  with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms · CPC title