1, 1′ -bis(phosphino)ferrocene ligands for alkoxycarbonylation

1. A diastereomerically pure compound having formula (I)

where

R 2 , R 4 are each independently selected from —(C 1 -C 12 )-alkyl, —(C 3 -C 12 )-cycloalkyl, —(C 3 -C 12 )-heterocycloalkyl, or —(C 6 -C 20 )-aryl;

the R 1 , R 3 radicals are each a —(C 3 -C 20 )-heteroaryl radical;

R 1 and R 3 each independently may be substituted by one or more substituents selected from —(C 1 -C 12 )-alkyl, —(C 3 -C 12 )-cycloalkyl, —(C 3 -C 12 )-heterocycloalkyl, —O—(C 1 -C 12 )-alkyl, —O—(C 1 -C 12 )-alkyl-(C 6 -C 20 )-aryl, —O—(C 3 -C 12 )-cycloalkyl, —S—(C 1 -C 12 )-alkyl, —S—(C 3 -C 12 )-cycloalkyl, —COO—(C 1 -C 12 )-alkyl, —COO—(C 3 -C 12 )-cycloalkyl, —CONH—(C 1 -C 12 )-alkyl, —CONH—(C 3 -C 12 )-cycloalkyl, —CO—(C 1 -C 12 )-alkyl, —CO—(C 3 -C 12 )-cycloalkyl, —N—[(C 1 -C 12 )-alkyl] 2 , —(C 6 -C 20 )-aryl, —(C 6 -C 20 )-aryl-(C 1 -C 12 )-alkyl, —(C 6 -C 20 )-aryl-O—(C 1 -C 12 )-alkyl, —(C 3 -C 20 )-heteroaryl, —(C 3 -C 20 )-heteroaryl-(C 1 -C 12 )-alkyl, —(C 3 -C 20 )-heteroaryl-O—(C 1 -C 12 )-alkyl, —COOH, —OH, —SO 3 H, —NH 2 , or halogen; and

R 2 , R 4 , if they are —(C 1 -C 12 )-alkyl, —(C 3 -C 12 )-cycloalkyl, —(C 3 -C 12 )-heterocycloalkyl or —(C 6 -C 20 )-aryl, may each independently be substituted by one or more substituents selected from —(C 1 -C 12 )-alkyl, —(C 3 -C 12 )-cycloalkyl, —(C 3 -C 12 )-heterocycloalkyl, —O—(C 1 -C 12 )-alkyl, —O—(C 1 -C 12 )-alkyl-(C 6 -C 20 )-aryl, —O—(C 3 -C 12 )-cycloalkyl, —S—(C 1 -C 12 )-alkyl, —S—(C 3 -C 12 )-cycloalkyl, —COO—(C 1 -C 12 )-alkyl, —COO—(C 3 -C 12 )-cycloalkyl, —CONH—(C 1 -C 12 )-alkyl, —CONH—(C 3 -C 12 )-cycloalkyl, —CO—(C 1 -C 12 )-alkyl, —CO—(C 3 -C 12 )-cycloalkyl, —N—[(C 1 -C 12 )-alkyl] 2 , —(C 6 -C 20 )-aryl, —(C 6 -C 20 )-aryl-(C 1 -C 12 )-alkyl, —(C 6 -C 20 )-aryl-O—(C 1 -C 12 )-alkyl, —(C 3 -C 20 )-heteroaryl, —(C 3 -C 20 -heteroaryl-(C 1 -C 12 )-alkyl, —(C 3 -C 20 )-heteroaryl-O—(C 1 -C 12 )-alkyl, —COOH, —OH, —SO 3 H, —NH 2 , or halogen.

2. The compound according to claim 1 ,

where R 2 , R 4 are each independently selected from —(C 1 -C 12 )-alkyl, cyclohexyl or phenyl.

3. The compound according to claim 1 ,

where the R 1 , R 3 are each a heteroaryl radical having five to ten ring atoms.

4. The compound according to claim 1 ,

where R 1 , R 3 are each independently selected from furyl, thienyl, pyrrolyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, imidazolyl, pyrazolyl, furazanyl, tetrazolyl, pyridyl, pyridazinyl, pyrimidyl, pyrazinyl, benzofuranyl, indolyl, isoindolyl, benzimidazoiyl, quinolyl, or isoquinolyl.

5. The compound according to claim 1 ,

where R 1 and R 3 are each pyridyl.

6. The compound according to claim 1 ,

where R 1 and R 3 are each identical radicals and R 2 and R 4 are each identical radicals.

7. The compound according to claim 1 having the formula:

8. A complex comprising Pd and the compound according to claim 1 .

9. A process comprising:

a) initially charging an ethylenically unsaturated compound;

b)adding a complex comprising the compound according to claim 1 and Pd;

c) adding an alcohol;

d) feeding in CO to form a reaction mixture;

e) heating the reaction mixture, with conversion of the ethylenically unsaturated compound to an ester.

10. The process according to claim 9 ,

wherein the ethylenically unsaturated compound comprises 2 to 30 carbon atoms and optionally one or more functional groups selected from carboxyl, thiocarboxyl, sulpho, sulphinyl, carboxylic anhydride, imide, carboxylic ester, sulphonic ester, carbamoyl, sulphamoyl, cyano, carbonyl, carbonothioyl, hydroxyl, sulphhydryl, amino, ether, thioether, aryl, heteroaryl or silyl groups and/or halogen substituents.

11. The process according to claim 9 ,

wherein the ethylenically unsaturated compound is selected from ethene, propene, 1-butene, cis- and/or trans-2-butene, isobutane, 1,3-butadiene, 1-pentene, cis- and/or trans-2-pentene, 2-methyl-1-butene, 3-methyl-1-butene, 2-methyl-2-butene, hexene, tetramethylethylene, heptene, 1-octene, 2-octene, di-n-butene, and mixtures thereof.

12. The process according to claim 9 ,

wherein the ethylenically unsaturated compound comprises 6 to 22 carbon atoms.

13. The process according to claim 9 ,

wherein the compound comprising Pd in process step b) is selected from palladium dichloride, palladium(II) acetylacetonate, palladium(II) acetate, dichloro(1,5-cyclooctadiene)palladium(II), bis(dibenzylideneacetone)palladium, bis(acetonitrile)dichloropalladium(II), or palladium(cinnamyl) dichloride.

14. Process according to claim 9 ,

wherein the alcohol in process step c) is selected from the group consisting of methanol, ethanol, 1-propanol, 1-butanol, 1-pentanol, 1-hexanol, 2-propanol, tert-butanol, 3-pentanol, cyclohexanol, phenol, and mixtures thereof.

15. A process for the catalysis of an aikoxycarbonylation reaction, comprising introducing a compound according to claim 1 .

16. A process for the catalysis of an alkoxycarbonylation reaction, comprising introducing a complex according to claim 8 .

17. The process comprising:

a) initially charging an ethylenically unsaturated compound;

b)adding the complex according to claim 8 ;

c) adding an alcohol;

d) feeding in CO;

e) heating the reaction mixture, with conversion of the ethylenica unsaturated compound to an ester.

18. The process according to claim 17 ,

wherein the ethylenically unsaturated compound comprises 2 to 30 carbon atoms and optionally one or more functional groups selected from carboxyl, thiocarboxyl, sulpho, sulphinyl, carboxylic anhydride, imide, carboxylic ester, sulphonic ester, carbamoyl, sulphamoyl, cyano, carbonyl, carbonothioyl, hydroxyl, sulphhydryl, amino, ether, thioether, aryl, heteroaryl or silyl groups and/or halogen substituents.

19. The process according to claim 17 ,

wherein the ethylenically unsaturated compound is selected from ethene, propene, 1-butene, cis- and/or trans-2-butene, isobutane, 1,3-butadiene, 1-pentene, cis- and/or trans-2-pentene, 2-methyl-1-butene, 3-methyl-1-butene, 2-methyl-2-butene, hexene, tetramethylethylene, heptene, 1-octene, 2-octene, di-n-butene, and mixtures thereof.

20. The process according to claim 17 ,

wherein the ethylenically unsaturated compound comprises 6 to 22 carbon atoms.