Monophosphine compounds and palladium catalysts based thereon for the alkoxycarbonylation of ethylenically unsaturated compounds

1. Compound of formula (I)

where

R 1 is selected from the group consisting of —(C 1 -C 12 )-alkyl, —(C 3 -C 12 )-cycloalkyl and —(C 3 -C 12 )-heterocycloalkyl;

R 2 is selected from the group consisting of phenyl, pyrimidyl and 2-imidazolyl;

R 3 is 2-imidazolyl;

and R 1 , R 2 and R 3 may each independently be substituted by one or more substituents selected from the group consisting of —(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-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 and halogen.

2. Compound according to claim 1 ,

where R 1 is —(C 1 -C 12 )-alkyl.

3. A compound having formulae (1)

4. Complex comprising Pd and a compound of formula (I)

where

R 1 is selected from the group consisting of —(C 1 -C 12 )-alkyl, —(C 3 -C 12 )-cycloalkyl and —(C 3 -C 12 )-heterocycloalkyl;

R 2 is selected from the group consisting of phenyl, pyrimidyl and 2-imidazolyl;

R 3 is imidazolyl;

and R 1 , R 2 and R 3 may each independently be substituted by one or more substituents selected from the group consisting of —(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-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 and halogen.

5. Process comprising the following process steps:

a) initially charging an ethylenically unsaturated compound;

b) adding a compound of formula (I)

where

R 1 is selected from the group consisting of —(C 1 -C 12 )-alkyl, —(C 3 -C 12 )-cycloalkyl and —(C 3 -C 12 )-heterocycloalkyl;

R 2 is selected from the group consisting of phenyl, pyrimidyl and 2-imidazolyl;

R 3 is imidazolyl;

and R 1 , R 2 and R 3 may each independently be substituted by one or more substituents selected from the group consisting of —(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-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 and halogen, and a compound comprising Pd,

or adding a complex according to claim 4 ;

c) adding an alcohol;

d) feeding in CO;

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

6. Process according to claim 5 ,

wherein the ethylenically unsaturated compound is selected from the group consisting of ethene, propene, 1-butene, cis- and/or trans-2-butene, isobutene, 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.

7. Process according to claim 5 ,

wherein the compound comprising Pd in process step b) is selected from the group consisting of palladium dichloride, palladium(II) acetylacetonate, palladium(II) acetate, dichloro(1,5-cycloocta-diene)palladium(II), bis(dibenzylideneacetone)palladium, bis(acetonitrile)dichloro-palladium(II) and palladium(cinnamyl) dichloride.

8. Process according to claim 5 ,

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.

9. Process according to claim 5 , wherein the alcohol in process step c) is an aliphatic alcohol.

10. A process for catalysis of an alkoxycarbonylation reaction, comprising: introducing a compound of formula (I)

where

R 1 is selected from the group consisting of —(C 1 -C 12 )-alkyl, —(C 3 -C 12 )-cycloalkyl and —(C 3 -C 12 )-heterocycloalkyl;

R 2 is selected from the group consisting of phenyl, pyrimidyl and 2-imidazolyl;

R 3 is imidazolyl;

and R 1 , R 2 and R 3 may each independently be substituted by one or more substituents selected from the group consisting of

—(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-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 and halogen or a complex according to claim 4 .