Catalyst-controlled aliphatic C—H oxidations

Patent metadata

Field	Value
Publication number	US-9925528-B2
Application number	US-201414916966-A
Country	US
Kind code	B2
Filing date	Sep 9, 2014
Priority date	Sep 9, 2013
Publication date	Mar 27, 2018
Grant date	Mar 27, 2018

Abstract

The invention provides simple small molecule, non-heme iron catalyst systems with broad substrate scope that can predictably enhance or overturn a substrate's inherent reactivity preference for sp3-hybridized C—H bond oxidation. The invention also provides methods for selective aliphatic C—H bond oxidation. Furthermore, a structure-based catalyst reactivity model is disclosed that quantitatively correlates the innate physical properties of the substrate to the site-selectivities observed as a function of the catalyst. The catalyst systems can be used in combination with oxidants such as hydrogen peroxide to effect highly selective oxidations of unactivated sp3 C—H bonds over a broad range of substrates.

First claim

What is claimed is:

1. A composition comprising a complex of Formula (I):

where X is a counterion;
n is 2 or 3;
L 1 and L 2 are ligands;
each Z is independently H or CF 3 ;
R 1 , R 2 , R 7 and R 8 are each independently an alkyl group, or a heteroalkyl group;
R 3 , R 4 , R 5 and R 6 are each independently hydrogen, halo, alkyl, or heteroalkyl;
C A and C B are carbon atoms and N A and N B are nitrogen atoms, where the superscript on the atoms denotes their separate locations;
C A and N A , in combination with one pair of groups selected from the group consisting of R 1 and R 3 , R 1 and R 4 , R 2 and R 3 , and R 2 and R 4 , form a pyrrolidine ring; and
C B and N B , in combination with one pair of groups selected from the group consisting of R 8 and R 6 , R 8 and R 5 , R 7 and R 6 , and R 7 and R 5 , form a pyrrolidine ring; and
wherein C A and C B , together with at least one pair of groups selected from the group consisting of R 3 and R 5 , R 4 and R 6 , R 4 and R 5 , and R 3 and R 6 , optionally form a cyclopentanyl ring.

2. The composition of claim 1 wherein the complex of Formula (I) is an (S,S) enantiomer.

3. The composition of claim 1 wherein the complex of Formula (I) is an (R,R) enantiomer.

4. The composition of claim 1 wherein X is Cl − , Br − , AcO − , TfO − , CF 3 CO 2 − , BF 4 − , ClO 4 − , ReO 4 − , AsF 6 − , or SbF 6 − .

5. The composition of claim 1 wherein L 1 and L 2 are independently acetone, acetonitrile, or a μ-oxo bridge.

6. The composition of claim 1 wherein R 1 , R 2 , R 7 and R 8 are each independently an alkyl group, and R 3 , R 4 , R 5 and R 6 are each independently hydrogen or alkyl.

7. The composition of claim 1 in combination with an oxidant.

8. The composition of claim 7 wherein the oxidant is hydrogen peroxide, ozone, a peracid, an alkyl hydroperoxide, or a periodinane.

9. The composition of claim 1 wherein the complex of Formula (I) is a complex of Formula (II):

wherein X is a counterion selected from the group consisting of Cl − , Br − , AcO − , TfO − , CF 3 CO 2 − , BF 4 − , ClO 4 − , ReO 4 − , AsF 6 − , and SbF 6 − ;
n is 2 or 3;
each Z is independently H or CF 3 ; and
L 1 and L 2 are ligands, wherein the ligands are each independently acetone, acetonitrile, or a μ-oxo bridge; or L 1 and L 2 together are a carboxylate group.

10. The composition of claim 9 wherein the complex of Formula (II) is the (S,S) enantiomer or the (R,R) enantiomer.

11. The complex (R,R)-Fe(CF3-PDP):

or its (S,S) enantiomer;
wherein X is a counterion selected from the group consisting of Cl − , Br − , AcO − , TfO − , CF 3 CO 2 − , BF 4 − , ClO 4 − , ReO 4 − , AsF 6 − , and SbF 6 − ; n is 2 or 3; and L 1 and L 2 are acetonitrile.

12. The complex (R,R)-Fe(tri-CF3-PDP):

or its (S,S) enantiomer;
wherein X is a counterion selected from the group consisting of Cl − , Br − , AcO − , TfO − , CF 3 CO 2 − , BF 4 − , ClO 4 − , ReO 4 − , AsF 6 − , and SbF 6 − ; n is 2 or 3; and L 1 and L 2 are acetonitrile.

13. A method of oxidizing an organic substrate comprising contacting a substrate and an oxidant in a first reaction mixture, wherein the first reaction mixture comprises a composition of claim 1 , thereby oxidizing the organic substrate to provide an oxidized product.

14. The method of claim 13 wherein the oxidant is hydrogen peroxide, ozone, a peracid, an alkyl hydroperoxide, or a periodinane.

15. The method of claim 13 wherein the first reaction mixture further comprises a solvent comprising acetonitrile.

16. The method of claim 13 wherein providing the oxidized product comprises providing a mono-oxidized product in a yield of at least about 40%.

17. A method of selectively oxidizing an sp 3 -hybridized C—H bond in a molecule comprising:
contacting a substrate having an sp 3 -hybridized C—H bond and an oxidant in a first reaction mixture in the presence of a composition of claim 1 , thereby selectively oxidizing an sp 3 -hybridized C—H bond in the molecule to provide an oxidized product.

Assignees

• Univ Illinois

Inventors

• White M Christina
• Gormisky Paul E

Classifications

• C07B33/00

  Oxidation in general · CPC title

• Y02P20/582

  Recycling of unreacted starting or intermediate materials · CPC title

• G06F19/702

  Physics · mapped topic

• B01J2531/0258

  Flexible ligands, e.g. mainly sp3-carbon framework as exemplified by the "tedicyp" ligand, i.e. cis-cis-cis-1,2,3,4-tetrakis(diphenylphosphinomethyl)cyclopentane · CPC title

• B01J31/1815 Primary

  with more than one complexing nitrogen atom, e.g. bipyridyl, 2-aminopyridine · CPC title