Iridium catalyst complexes and C—H bond activated products therefrom

Patent metadata

Field	Value
Publication number	US-9289759-B2
Application number	US-201213611089-A
Country	US
Kind code	B2
Filing date	Sep 12, 2012
Priority date	Sep 13, 2011
Publication date	Mar 22, 2016
Grant date	Mar 22, 2016

Abstract

Provided is a novel iridium catalyst complex which is useful in the dehydrogenation of alkanes. The iridium complex comprises the metal iridium atom complexed with a benzimidazolyl-containing ligand. The iridium atom can be coordinated with the nitrogen atoms in the benzimidazolyl-containing ligand to form an NCN pincer ligand complex. In another embodiment, the iridium catalyst is used, with or without a co-catalyst, in a dehydrogenation reaction converting alkanes to olefins. The reaction can be in a closed or open system, and can be run in a liquid or gaseous phase.

First claim

That which is claimed is:

1. An iridium catalyst complex of the formula LMX(X′) n , where n =0, 1 or 2;
X and X′ are moieties which can be eliminated from the metal center to generate a catalytically active LM fragment;
M is iridium; and
L is the ligand 2,2′-(1,3-phenylene) bis (1-propylbenzimidazol 2 yl).

2. A catalyst composition comprising the iridium catalyst complex of claim 1 and a co-catalyst.

3. A method of dehydrogenating alkanes which comprises contacting an alkane under dehydrogenation conditions in the presence of an iridium catalyst complex of the formula LMX(X′) n , where n =0, 1 or 2;
X and X′ are moieties which can be eliminated from the metal center to generate a catalytically active LM fragment;
M is iridium; and
L is a ligand having the formula:

wherein A and A′ are independently selected from the group consisting of:

where R 1 , R 2 ,R 3 , and R* are independently selected from the group consisting of halides, hydride, triflate, acetates, borates, C 1 through C 12 alky, C 1 through C 12 alkoxy, C 3 through C 12 cycloalkyl, C 3 through C 12 cycloalkoxy, C 6 through C 14 aryl and C 7 through C 17 aralkyl olefins;
and Y is selected from the group consisting of C—H, C—C 1 , C—Br, C—I, N, P, C—OR 4 wherein R 4 is hydrogen, an optionally substituted acyl group, an optionally substituted alkylsulfonyl group or other leaving group; and p=0,1 or 2.

4. A method of dehydrogenating alkanes which comprises contacting an alkane under dehydrogenation conditions in the presence of the catalyst of claim 1 .

5. The method of claim 3 , wherein the reaction is run with a high boiling alkane having a boiling point of at least 200° C., in an open reactor.

6. The method of claim 5 , wherein the alkane is a C 12 or higher alkane.

7. The method of claim 3 , wherein the dehydrogenation reaction is run in the presence of oxygen.

8. The method of claim 3 , wherein the reaction is run in a closed system.

9. The method of claim 8 , wherein the reaction is run with an alkane which is lower than a C 12 alkane.

10. The method of claim 3 , wherein the alkane is a C 4 - C 20 alkane.

11. The method of claim 3 , wherein an olefin product is recovered.

12. The method of claim 7 , wherein the contacting is conducted in the gaseous phase.

13. The method of claim 4 , wherein a co-catalyst is used for the contacting.

Assignees

• Goldman Alan Stuart
• Stibrany Robert Timothy
• Univ Rutgers

Inventors

• Goldman Alan Stuart
• Stibrany Robert Timothy

Classifications

• C07C5/52

  with a hydrocarbon as an acceptor, e.g. hydrocarbon disproportionation, i.e. 2CnHp -> CnHp+q + CnHp-q · CPC title

• C07C5/333 Primary

  Catalytic processes · CPC title

• C07C11/12

  Alkadienes · CPC title

• C07F15/004

  without a metal-carbon linkage · CPC title

• C07C11/02

  Alkenes · CPC title