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

Abstract

The invention relates to a compound of formula (I) ##STR00001##
where R.sup.1 and R.sup.3 are each a heteroaryl radical having five ring atoms, R.sup.2 and R.sup.4 are each independently selected from (C.sub.1-C.sub.12)-alkyl, (C.sub.3-C.sub.12)-cycloalkyl, (C.sub.3-C.sub.12)-heterocycloalkyl, (C.sub.6-C.sub.20)-aryl; R.sup.1 and R.sup.3 may each independently be substituted by one or more substituents selected from (C.sub.1-C.sub.12)-alkyl, (C.sub.3-C.sub.12)-cycloalkyl, (C.sub.3-C.sub.12)-heterocycloalkyl, O(C.sub.1-C.sub.12)-alkyl, O(C.sub.1-C.sub.12)-alkyl-(C.sub.6-C.sub.20)-aryl, O(C.sub.3-C.sub.12)-cycloalkyl, S(C.sub.1-C.sub.12)-alkyl, S(C.sub.3-C.sub.12)-cycloalkyl, COO(C.sub.1-C.sub.12)-alkyl, COO(C.sub.3-C.sub.12)-cycloalkyl, CONH(C.sub.1-C.sub.12)-alkyl, CONH(C.sub.3-C.sub.12)-cycloalkyl, CO(C.sub.1-C.sub.12)-alkyl, CO(C.sub.3-C.sub.12)-cycloalkyl, N[(C.sub.1-C.sub.12)-alkyl].sub.2, (C.sub.6-C.sub.20)-aryl, (C.sub.6-C.sub.20)-aryl-(C.sub.1-C.sub.12)-alkyl, (C.sub.6-C.sub.20)-aryl-O(C.sub.1-C.sub.12)-alkyl, (C.sub.3-C.sub.20)-heteroaryl, (C.sub.3-C.sub.20)-heteroaryl-(C.sub.1-C.sub.12)-alkyl, (C.sub.3-C.sub.20)-heteroaryl-O(C.sub.1-C.sub.12)-alkyl, COOH, OH, SO.sub.3H, NH.sub.2, halogen; and R.sup.2 and R.sup.4, if they are (C.sub.1-C.sub.12)-alkyl, (C.sub.3-C.sub.12)-cycloalkyl, (C.sub.3-C.sub.12)-heterocycloalkyl or (C.sub.6-C.sub.20)-aryl, may each independently be substituted by one or more substituents selected from (C.sub.1-C.sub.12)-alkyl, (C.sub.3-C.sub.12)-cycloalkyl, (C.sub.3-C.sub.12)-heterocycloalkyl, O(C.sub.1-C.sub.12)-alkyl, O(C.sub.1-C.sub.12)-alkyl-(C.sub.6-C.sub.20)-aryl, O(C.sub.3-C.sub.12)-cycloalkyl, S(C.sub.1-C.sub.12)-alkyl, S(C.sub.3-C.sub.12)-cycloalkyl, COO(C.sub.1-C.sub.12)-alkyl, COO(C.sub.3-C.sub.12)-cycloalkyl, CONH(C.sub.1-C.sub.12)-alkyl, CONH(C.sub.3-C.sub.12)-cycloalkyl, CO(C.sub.1-C.sub.12)-alkyl, CO(C.sub.3-C.sub.12)-cycloalkyl, N[(C.sub.1-C.sub.12)-alkyl].sub.2, (C.sub.6-C.sub.20)-aryl, (C.sub.6-C.sub.20)-aryl-(C.sub.1-C.sub.12)-alkyl, (C.sub.6-C.sub.20)-aryl-O(C.sub.1-C.sub.12)-alkyl, (C.sub.3-C.sub.20)-heteroaryl, (C.sub.3-C.sub.20)-heteroaryl-(C.sub.1-C.sub.12)-alkyl, (C.sub.3-C.sub.20)-heteroaryl-O(C.sub.1-C.sub.12)-alkyl, COOH, OH, SO.sub.3H, NH.sub.2, halogen;
excluding the compounds of the formulae (1) and (2) ##STR00002## The invention further relates to precursors for preparation of the compound according to the invention, to Pd complexes comprising the compound according to the invention and to the use thereof in alkoxycarbonylation.

Claims

1. A compound of formula (I) ##STR00021## where R.sup.1 and R.sup.4 are each a heteroaryl radical having five ring atoms, R.sup.2 and R.sup.3 are each independently selected from (C.sub.1-C.sub.12)-alkyl, (C.sub.3-C.sub.12)-cycloalkyl, (C.sub.3-C.sub.12)-heterocycloalkyl, or (C.sub.6-C.sub.20)-aryl; R.sup.1 and R.sup.4 may each independently be substituted by one or more substituents selected from (C.sub.1-C.sub.12)-alkyl, (C.sub.3-C.sub.12)-cycloalkyl, (C.sub.3-C.sub.12)-heterocycloalkyl, O(C.sub.1-C.sub.12)-alkyl, O(C.sub.1-C.sub.12)-alkyl-(C.sub.6-C.sub.20)-aryl, O(C.sub.3-C.sub.12)-cycloalkyl, S(C.sub.1-C.sub.12)-alkyl, S(C.sub.3-C.sub.12)-cycloalkyl, COO(C.sub.1-C.sub.12)-alkyl, COO(C.sub.3-C.sub.12)-cycloalkyl, CONH(C.sub.1-C.sub.12)-alkyl, CONH(C.sub.3-C.sub.12)-cycloalkyl, CO(C.sub.1-C.sub.12)-alkyl, CO(C.sub.3-C.sub.12)-cycloalkyl, N[(C.sub.1-C.sub.12)-alkyl].sub.2, (C.sub.6-C.sub.20)-aryl, (C.sub.6-C.sub.20)-aryl-(C.sub.1-C.sub.12)-alkyl, (C.sub.6-C.sub.20)-aryl-O(C.sub.1-C.sub.12)-alkyl, (C.sub.3-C.sub.20)-heteroaryl, (C.sub.3-C.sub.20)-heteroaryl-(C.sub.1-C.sub.12)-alkyl, (C.sub.3-C.sub.20)-heteroaryl-O(C.sub.1-C.sub.12)-alkyl, COOH, OH, SO.sub.3H, NH.sub.2, or halogen; and R.sup.2 and R.sup.3, if they are (C.sub.1-C.sub.12)-alkyl, (C.sub.3-C.sub.12)-cycloalkyl, (C.sub.3-C.sub.12)-heterocycloalkyl or (C.sub.6-C.sub.20)-aryl, may each independently be substituted by one or more substituents selected from (C.sub.1-C.sub.12)-alkyl, (C.sub.3-C.sub.12)-cycloalkyl, (C.sub.3-C.sub.12)-heterocycloalkyl, O(C.sub.1-C.sub.12)-alkyl, O(C.sub.1-C.sub.12)-alkyl-(C.sub.6-C.sub.20)-aryl, O(C.sub.3-C.sub.12)-cycloalkyl, S(C.sub.1-C.sub.12)-alkyl, S(C.sub.3-C.sub.12)-cycloalkyl, COO(C.sub.1-C.sub.12)-alkyl, COO(C.sub.3-C.sub.12)-cycloalkyl, CONH(C.sub.1-C.sub.12)-alkyl, CONH(C.sub.3-C.sub.12)-cycloalkyl, CO(C.sub.1-C.sub.12)-alkyl, CO(C.sub.3-C.sub.12)-cycloalkyl, N[(C.sub.1-C.sub.12)-alkyl].sub.2, (C.sub.6-C.sub.20)-aryl, (C.sub.6-C.sub.20)-aryl-(C.sub.1-C.sub.12)-alkyl, (C.sub.6-C.sub.20)-aryl-O(C.sub.1-C.sub.12)-alkyl, (C.sub.3-C.sub.20)-heteroaryl, (C.sub.3-C.sub.20)-heteroaryl-(C.sub.1-C.sub.12)-alkyl, (C.sub.3-C.sub.20)-heteroaryl-O(C.sub.1-C.sub.12)-alkyl, COOH, OH, SO.sub.3H, NH.sub.2, or halogen; excluding the compounds of formulae (1) and (2) ##STR00022##

2. The compound according to claim 1, where R.sup.1 and R.sup.4 are each independently selected from furyl, thienyl, 2-pyrrolyl, 4-imidazolyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, pyrazolyl, furazanyl, or tetrazolyl.

3. The compound according to claim 1, where R.sup.1 and R.sup.4 are each independently selected from the group consisting of furyl and thienyl.

4. The compound according to claim 1, where R.sup.2 and R.sup.3 are each independently selected from the group consisting of (C.sub.1-C.sub.12)-alkyl, (C.sub.3-C.sub.12)-cycloalkyl and (C.sub.6-C.sub.20)-aryl.

5. The compound according to claim 1, where R.sup.2 and R.sup.3 are each (C.sub.1-C.sub.12)-alkyl.

6. The compound according to claim 1, where R.sup.1 and R.sup.4 may each independently be substituted by one or more substituents selected from (C.sub.1-C.sub.12)-alkyl, (C.sub.3-C.sub.12)-cycloalkyl, O(C.sub.1-C.sub.12)-alkyl, O(C.sub.1-C.sub.12)-alkyl-(C.sub.6-C.sub.20)-aryl, O(C.sub.3-C.sub.12)-cycloalkyl, (C.sub.6-C.sub.20)-aryl, (C.sub.6-C.sub.20)-aryl, (C.sub.1-C.sub.12)-alkyl, or (C.sub.6-C.sub.20)-aryl-O(C.sub.1-C.sub.12)-alkyl.

7. The compound according to claim 1, where R.sup.2 and R.sup.3, if they are (C.sub.1-C.sub.12)-alkyl, (C.sub.3-C.sub.12)-cycloalkyl, (C.sub.3-C.sub.12)-heterocycloalkyl or (C.sub.6-C.sub.20)-aryl, may each independently be substituted by one or more substituents selected from (C.sub.1-C.sub.12)-alkyl, (C.sub.3-C.sub.12)-cycloalkyl, O(C.sub.1-C.sub.12)-alkyl, O(C.sub.1-C.sub.12)-alkyl-(C.sub.6-C.sub.20)-aryl, O(C.sub.3-C.sub.12)-cycloalkyl, (C.sub.6-C.sub.20)-aryl, (C.sub.6-C.sub.20)-aryl-(C.sub.1-C.sub.12)-alkyl, or (C.sub.6-C.sub.20)-aryl-O(C.sub.1-C.sub.12)-alkyl.

8. The compound according to claim 1, of one of formulae (16), (22) and (34) ##STR00023##

9. A complex comprising Pd and a compound according to claim 1.

10. A process for alkoxylation of long-chain olefins comprising the following process steps: a) initially charging an ethylenically unsaturated compound; b) adding a compound of formula (I) ##STR00024## where R.sup.1 and R.sup.4 are each a heteroaryl radical having five ring atoms, R.sup.2 and R.sup.3 are each independently selected from (C.sub.1-C.sub.12)-alkyl, (C.sub.3-C.sub.12)-cycloalkyl, (C.sub.3-C.sub.12)-heterocycloalkyl, or (C.sub.6-C.sub.20)-aryl; R.sup.1 and R.sup.4 may each independently be substituted by one or more substituents selected from (C.sub.1-C.sub.12)-alkyl, (C.sub.3-C.sub.12)-cycloalkyl, (C.sub.3-C.sub.12)-heterocycloalkyl, O(C.sub.1-C.sub.12)-alkyl, O(C.sub.1-C.sub.12)-alkyl-(C.sub.6-C.sub.20)-aryl, O(C.sub.3-C.sub.12)-cycloalkyl, S(C.sub.1-C.sub.12)-alkyl, S(C.sub.3-C.sub.12)-cycloalkyl, COO(C.sub.1-C.sub.12)-alkyl, COO(C.sub.3-C.sub.12)-cycloalkyl, CONH(C.sub.1-C.sub.12)-alkyl, CONH(C.sub.3-C.sub.12)-cycloalkyl, CO(C.sub.1-C.sub.12)-alkyl, CO(C.sub.3-C.sub.12)-cycloalkyl, N[(C.sub.1-C.sub.12)-alkyl].sub.2, (C.sub.6-C.sub.20)-aryl, (C.sub.6-C.sub.20)-aryl-(C.sub.1-C.sub.12)-alkyl, (C.sub.6-C.sub.20)-aryl-O(C.sub.1-C.sub.12)-alkyl, (C.sub.3-C.sub.20)-heteroaryl, (C.sub.3-C.sub.20)-heteroaryl-(C.sub.1-C.sub.12)-alkyl, (C.sub.3-C.sub.20)-heteroaryl-O(C.sub.1-C.sub.12)-alkyl, COOH, OH, SO.sub.3H, NH.sub.2, or halogen; and R.sup.2 and R.sup.3, if they are (C.sub.1-C.sub.12)-alkyl, (C.sub.3-C.sub.12)-cycloalkyl, (C.sub.3-C.sub.12)-heterocycloalkyl or (C.sub.6-C.sub.20)-aryl, may each independently be substituted by one or more substituents selected from (C.sub.1-C.sub.12)-alkyl, (C.sub.3-C.sub.12)-cycloalkyl, (C.sub.3-C.sub.12)-heterocycloalkyl, O(C.sub.1-C.sub.12)-alkyl, O(C.sub.1-C.sub.12)-alkyl-(C.sub.6-C.sub.20)-aryl, O(C.sub.3-C.sub.12)-cycloalkyl, S(C.sub.1-C.sub.12)-alkyl, S(C.sub.3-C.sub.12)-cycloalkyl, COO(C.sub.1-C.sub.12)-alkyl, COO(C.sub.3-C.sub.12)-cycloalkyl, CONH(C.sub.1-C.sub.12)-alkyl, CONH(C.sub.3-C.sub.12)-cycloalkyl, CO(C.sub.1-C.sub.12)-alkyl, CO(C.sub.3-C.sub.12)-cycloalkyl, N[(C.sub.rC.sub.12)-alkyl].sub.2, (C.sub.6-C.sub.20)-aryl, (C.sub.6-C.sub.20)-aryl-(C.sub.1-C.sub.12)-alkyl, (C.sub.6-C.sub.20)-aryl-O(C.sub.1-C.sub.12)-alkyl, (C.sub.3-C.sub.20)-heteroaryl, (C.sub.3-C.sub.20)-heteroaryl-(C.sub.1-C.sub.12)-alkyl, (C.sub.3-C.sub.20)-heteroaryl-O(C.sub.1-C.sub.12)-alkyl, COOH, OH, SO.sub.3H, NH.sub.2, or halogen; excluding the compounds of formulae (1) and (2) ##STR00025## and a compound comprising Pd, or adding a complex according to claim 9; c) adding an alcohol; d) feeding in CO; e) heating the reaction mixture, with conversion of the ethylenically unsaturated compound to an ester.

11. The process according to claim 10, 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.

12. The process according to claim 10, 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.

13. The process according to claim 10, 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.

14. A process for catalysis of an alkoxycarbonylation reaction, comprising: introducing a compound of formula (I) ##STR00026## where R.sup.1 and R.sup.4 are each a heteroaryl radical having five ring atoms, R.sup.2 and R.sup.3 are each independently selected from (C.sub.1-C.sub.12)-alkyl, (C.sub.3-C.sub.12)-cycloalkyl, (C.sub.3-C.sub.12)-heterocycloalkyl, or (C.sub.6-C.sub.20)-aryl; R.sup.1 and R.sup.4 may each independently be substituted by one or more substituents selected from (C.sub.1-C.sub.12)-alkyl, (C.sub.3-C.sub.12)-cycloalkyl, (C.sub.3-C.sub.12)-heterocycloalkyl, O(C.sub.1-C.sub.12)-alkyl, O(C.sub.1-C.sub.12)-alkyl-(C.sub.6-C.sub.20)-aryl, O(C.sub.3-C.sub.12)-cycloalkyl, S(C.sub.1-C.sub.12)-alkyl, S(C.sub.3-C.sub.12)-cycloalkyl, COO(C.sub.1-C.sub.12)-alkyl, COO(C.sub.3-C.sub.12-cycloalkyl, CONH(C.sub.1-C.sub.12)-alkyl, CONH(C.sub.3-C.sub.12)-cycloalkyl, CO(C.sub.1-C.sub.12)-alkyl, CO(C.sub.3-C.sub.12)-cycloalkyl, N[(C.sub.1-C.sub.12)-alkyl].sub.2, (C.sub.6-C.sub.20)-aryl, (C.sub.6-C.sub.20)-aryl-(C.sub.1-C.sub.12)-alkyl, (C.sub.6-C.sub.20)-aryl-O(C.sub.1-C.sub.12)-alkyl, (C.sub.3-C.sub.20)-heteroaryl, (C.sub.3-C.sub.20)-heteroaryl-(C.sub.1-C.sub.12)-alkyl, (C.sub.3-C.sub.20)-heteroaryl-O(C.sub.1-C.sub.12)-alkyl, COOH, OH, SO.sub.3H, NH.sub.2, or halogen; and R.sup.2 and R.sup.3, if they are (C.sub.1-C.sub.12)-alkyl, (C.sub.3-C.sub.12)-cycloalkyl, (C.sub.3-C.sub.12)-heterocycloalkyl or (C.sub.6-C.sub.20)-aryl, may each independently be substituted by one or more substituents selected from (C.sub.1-C.sub.12)-alkyl, (C.sub.3-C.sub.12)-cycloalkyl, (C.sub.3-C.sub.12)-heterocycloalkyl, O(C.sub.1-C.sub.12)-alkyl, O(C.sub.1-C.sub.12)-alkyl-(C.sub.6-C.sub.20)-aryl, O(C.sub.3-C.sub.12)-cycloalkyl, S(C.sub.1-C.sub.12)-alkyl, S(C.sub.3-C.sub.12)-cycloalkyl, COO(C.sub.1-C.sub.12)-alkyl, COO(C.sub.3-C.sub.12)-cycloalkyl, CONH(C.sub.1-C.sub.12)-alkyl, CONH(C.sub.3-C.sub.12)-cycloalkyl, CO(C.sub.1-C.sub.12)-alkyl, CO(C.sub.3-C.sub.12)-cycloalkyl, N[(C.sub.1-C.sub.12)-alkyl].sub.2, (C.sub.6-C.sub.20)-aryl, (C.sub.6-C.sub.20)-aryl-(C.sub.1-C.sub.12)-alkyl, (C.sub.6-C.sub.20)-aryl-O(C.sub.1-C.sub.12)-alkyl, (C.sub.3-C.sub.20)-heteroaryl, (C.sub.3-C.sub.20)-heteroaryl-(C.sub.1-C.sub.12)-alkyl, (C.sub.3-C.sub.20)-heteroaryl-O(C.sub.1-C.sub.12)-alkyl, COOH, OH, SO.sub.3H, NH.sub.2, or halogen; excluding the compounds of formulae (1) and (2) ##STR00027## or a complex according to claim 9.

Description

EXAMPLES

(1) The invention is described in detail hereinafter by working examples.

(2) General Procedures

(3) All the preparations which follow were carried out under protective gas using standard Schlenk techniques. The solvents were dried over suitable desiccants before use (Purification of Laboratory Chemicals, W. L. F. Armarego (Author), Christina Chai (Author), Butterworth Heinemann (Elsevier), 6th edition, Oxford 2009).

(4) Phosphorus trichloride (Aldrich) was distilled under argon before use. All preparative operations were effected in baked-out vessels. The products were characterized by means of NMR spectroscopy. Chemical shifts (?) are reported in ppm. The .sup.31P NMR signals were referenced as follows: SR.sub.31P=SR.sub.1H*(BF.sub.31P/BF.sub.1H)=SR.sub.1H*0.4048. (Robin K. Harris, Edwin D. Becker, Sonia M. Cabral de Menezes, Robin Goodfellow, and Pierre Granger, Pure Appl. Chem., 2001, 73, 1795-1818; Robin K. Harris, Edwin D. Becker, Sonia M. Cabral de Menezes, Pierre Granger, Roy E. Hoffman and Kurt W. Zilm, Pure Appl. Chem., 2008, 80, 59-84).

(5) The recording of nuclear resonance spectra was effected on Bruker Avance 300 or Bruker Avance 400, gas chromatography analysis on Agilent GC 7890A, elemental analysis on Leco TruSpec CHNS and Varian ICP-OES 715, and ESI-TOF mass spectrometry on Thermo Electron Finnigan MAT 95-XP and Agilent 6890 N/5973 instruments.

Preparation of Precursor G

tert-Butylchloro(furan-2-yl)phosphine

(6) ##STR00009## Chemicals used: 1.6 ml of tetramethylethylenediamine (TMEDA) (1.05 eq, 10 mmol) 6 ml of 1.6 M n-butyllithium (n-BuLi) (10 mmol, 1.05 eq) 1.5 g of dichloro(tert-butyl)phosphine (9.5 mmol) 0.7 ml of furan (9.7 mmol, 1.03 eq) Absolute diethyl ether

(7) 0.64 g (0.7 ml, 9.4 mmol) of furan are weighed out in a 50 ml three-neck flask with thermometer and dropping funnel under argon and dissolved in 10 ml of diethyl ether. Then 1.6 ml of tetramethylethylenediamine are added to the solution. The mixture is then cooled down to ?78? C. Thereafter, 6 ml of 1.6 N n-butyllithium solution in hexane are added dropwise by means of a dropping funnel. The 50 ml flask containing the reaction mixture is then left to stir at room temperature for 30 min. Subsequently, 1.5 g of tert-butyldichlorophosphine are dissolved in 20 ml of ether. The furan-n-BuLi mixture is added dropwise at ?78? C. to the tert-butyldichloro-phosphine solution. Thereafter, the mixture is warmed to room temperature. Lithium chloride precipitates out. The suspension is filtered and the ether solution is distilled under reduced pressure at 10.sup.?1 Torr. The product is a colourless oil.

(8) Yield 0.75 g, 42%

(9) B.p.=54? C. (10.sup.?1 Torr)

(10) Purity (NMR)=100%,

(11) .sup.31P NMR (CD.sub.2Cl.sub.2, 121 MHz)=80.92 ppm,

(12) .sup.13C NMR (CD.sub.2Cl.sub.2, 75 MHz)=151.1 d, J.sub.PC=56 Hz, 148.56 s, 123.65 d, J.sub.PC=30.2 Hz, 111 d, J.sub.PC=7.2 Hz, 35.4 d, J.sub.PC=24.9 Hz, 25.9 d, J.sub.PC=18.3 Hz

(13) .sup.1H NMR (CD.sub.2Cl.sub.2, 300 MHz, d1=10 s): 7.63, dd, (J=1.7 Hz, J=0.7 Hz, 1H), 6.87 td (J=2.5 Hz, J=1 Hz, 1H), 6.38 dt (J=4 Hz, J=1.7 Hz, 1H), 1.1 (d, J=14.8 Hz, 9H)

(14) GC MS (M/Z, I (%)): 190 (19), 155 (2.5), 133 (8.9), 99 (14), 69 (23.6), 57 (100), 41 (32.4)

Preparation of Precursor H

(15) ##STR00010## Chemicals used: 2.5 ml of TMEDA (16.6 mmol) 10 ml of 1,6 N n-butyllithium (15.7 mmol) 2.5 g of dichloro(tert-butyl)phosphine 1.2 ml of thiophene Absolute diethyl ether

(16) 1.2 ml of thiophene are weighed out in a 50 ml three-neck flask with thermometer and dropping funnel under argon and dissolved in 10 ml of diethyl ether. Then 2.5 ml of TMEDA are added to the solution. The mixture is then cooled down to ?78? C. Thereafter, 10 ml of 1.6 N n-butyllithium solution in hexane are added dropwise by means of a dropping funnel. The 50 ml flask containing the reaction mixture is subsequently left to stir at room temperature for 30 min. Subsequently, 2.5 g of tert-butyldichlorophosphine are dissolved in 20 ml of ether. Then the thiophene-n-BuLi mixture is added dropwise to the tert-butyldichlorophosphine solution at ?78? C. Thereafter, the mixture is warmed to room temperature. The ether solution is distilled under reduced pressure at 10.sup.?1 Torr. The product is a colourless oil.

(17) Yield 2.32 g, 70%

(18) B.p.=54? C. (10.sup.?1 Torr)

(19) Purity (NMR)=100%,

(20) .sup.31P NMR (CD.sub.2Cl.sub.2, 121 MHz)=99.8 ppm,

(21) .sup.13C NMR (CD.sub.2Cl.sub.2, 75 MHz)=1137.7 d, (J.sub.PC=59.9 Hz), 136.6 d (J.sub.PC=33 Hz), 133.1 s, 127.9 d (J.sub.PC=8.7 Hz), 35.1 d (J.sub.PC=28.1 Hz), 25.5 d (J.sub.PC=18.8 Hz), .sup.1H NMR (CD.sub.2Cl.sub.2, 300 MHz, 7.59 dddd (J=0.51, J=1.1, J=4.9, J=6.0 1H), 7.34 dddd (J=1.1, J=3.5, J=7.05, J=10.6 1H), 7.03, dddd, (J=1.3, J=3.5, J=6.2 J=8.4 1H), 1.0 d (J=14.7 Hz, 9H)

Preparation of Compound 10 (Comparative Compound)

(22) Proceeding from 1,1-(ferrocenediyl)phenylphosphine, the strained phosphine ring is opened with PhLi and the resulting intermediate is quenched with a chlorophosphine.

(23) ##STR00011##

(24) ##STR00012##

(25) A 50 ml round-bottom flask with magnetic stirrer bar and nitrogen connection is initially charged with 1.13 mmol (565 ?l) of phenyllithium (PhLi), and a solution of 1.03 mmol (300 mg) of cyclic phosphine in 20 ml of heptane is slowly added dropwise via a syringe pump. The Li salt is washed twice with heptane and admixed with 6 ml of heptane. A heptane solution of 0.8 eq (0.824 mmol, 131 ?l) of CIP/Pr.sub.2 in 7 ml of heptane is added dropwise to the suspension at room temperature. The red-brown suspension barely changes colour. After stirring for 20 min, the suspension is heated under reflux for 1.5 hours. The solid turns a somewhat lighter colour. Solvent is removed completely and the brown-red residue is taken up in H.sub.2O and ether. The organic phase is washed twice with H.sub.2O and dried over Na.sub.2SO.sub.4. A .sup.31P spectrum of the ether phase is recorded. The spectrum shows 2 singlets. The chlorophosphine has been fully consumed. The ether phase is dried and 300 mg (yield: 61%) of a brown-yellow oil are obtained, which dissolves in MeOH on a water bath at 65? C. The solution is put in the freezer (?78? C.) overnight. 76 mg of a brown-yellow oil precipitate out, which is analysed by NMR spectroscopy.

(26) .sup.1H NMR (300 MHz, CDCl.sub.3) ? 7.46-7.23 (m, 10H, Ph), 4.36 (m, 2H, Cp), 4.21 (m, 2H, Cp), 34.24 (m, 4H, Cp), 1.88 (m, 2H, iPr), 1.15-0.96 (m, 12H, iPr).

(27) .sup.13C NMR (75 MHz, CDCl.sub.3) ? 139.9 (J=9.8 Hz, Ph), 133.4 (J=19.2 Hz, Ph), 128.4, 128.1, 128.0 (Ph), 77.1, 76.8, 76.2, 76.1 (Cp), 73.5 (J=14.5 Hz, Cp), 72.8 (J=2.9 Hz, Cp), 71.9 (J=10.5 Hz, Cp), 72.1 (Cp), 23.3 (J=11.0 Hz, iPr), 20.1, 20.0, 19.9, 19.8 (iPr).

(28) .sup.31P NMR (121 MHz, C.sub.6D.sub.6) ?=0.88 and ?16.62

Preparation of Compound 16

1,1-Bis((tert-butyl-2-furanyl)phosphino)ferrocene

(29) ##STR00013##

(30) Chemicals used: 0.37 g of ferrocene (1.98 mmol) 2.2 ml of TMEDA (tetramethylethylenediamine) (7.34 mmol, 2.1 eq, 14.6 mmol) 10 ml of 1.6 N n-butyllithium (16 mmol, 2.28 eq) 0.75 g of chloro(tert-butyl-2-furanyl)phosphine (3.95 mmol) Absolute diethyl ether, degassed water, methanol under argon, G 60 silica gel

(31) In a 50 ml three-neck flask provided with a magnetic stirrer, 0.37 g of ferrocene is weighed out under argon, and 5 ml of absolute heptane are added. The ferrocene dissolves completely. Thereafter, 0.7 ml of tetramethylethylenediamine are added to the solution and then 2.9 ml of 1.6 N n-BuLi in hexane are added. The reaction solution is left to stand under cool conditions at room temperature overnight. A solid forms. The supernatant solution is removed. 10 ml of heptane are added to the solid. Then 0.75 g of tert-butylchloro(furan-2-yl)phosphine is dissolved in 5 ml of absolute THF and slowly added dropwise. This solution is stirred for one hour. Then the solvent is changed from heptane to 10 ml of diethyl ether by means of reduced pressure. Then the mixture is washed three times with 5 ml each time of water. The organic phase is dried over Na.sub.2SO.sub.4 (anhydrous). The solution is concentrated to 10 ml and column chromatography is conducted with ether. Subsequently, the solution is concentrated and crystallized from hot methanol. Orange crystals precipitate out. The liquid is decanted off and the crystals are dried.

(32) Yield: 0.7 g

(33) .sup.31P NMR (acetone-d.sub.6, 121 MHz)=18.3 s, s, ppm,

(34) .sup.13C NMR (acetone-d.sub.6, 75 MHz)=147.9 s, 147.8 s, 123.4 d, J.sub.PC=34.3 Hz, 111.0 d, J.sub.PC=9 Hz, 78.1 d, J.sub.PC=42.6 Hz 74.5 s, 72.99 s, 72.4 d, J.sub.PC=9.5 Hz, 69.61 s, 31.70 d, J.sub.PC=7.3 Hz, 28.4 d, J.sub.PC=14.8 Hz.

(35) .sup.1H NMR (acetone-d.sub.6, 300 MHz): 7.85-7.8 m (2H), 6.9-6.8 m (2H), 6.45-6.4 m (2H), 4.5 m (1.3H), 4.1 m (0.9H), 3.9 m (1.3H), 3.8 m (3.7H), 2.6 m (0.7H), 0.8 (quint, J=2.3 Hz, 18H)

(36) HRMS (ESI) m/z.sup.+ calculated for C.sub.26H.sub.32FeO.sub.2P.sub.2(M+H).sup.+ 495.13; found 495.12983.

Preparation of Compound 19 (Comparative Compound)

(37) ##STR00014##

(38) 0.93 g of ferrocene is dissolved in 50 ml of absolute heptane in a 100 ml three-neck flask provided with a thermometer, magnetic stirrer and reflux condenser. 1.3 g of TMEDA (1.6 ml) and 7.5 ml of 1.6 M n-BuLi/hexane are added by means of syringes at room temperature. The solution is left to stand for 5 hours. Orange/brown crystals of the dilithiated ferrocene precipitate out. The supernatant solution is removed by means of a syringe. And 20 ml of absolute heptane are added. Subsequently, the chlorophosphine dissolved in 10 ml of heptane is added dropwise. The mixture is heated under reflux for one hour. After cooling, the organic phase is washed three times with 10 ml each time of degassed water. The mixture is concentrated to dryness, and 10 ml of diethyl ether are added. The solution is filtered through 10 cm of silica gel 60 under argon with diethyl ether as solvent, concentrated to dryness and crystallized from a little hot methanol to give the target product in an about 50% non-optimized yield.

(39) Analysis:

(40) .sup.31P (121 MHz, CDCl.sub.3), ?7.8 s, ?8.15 s,

(41) .sup.13C (75 MHz, CDCl.sub.3); 137.77, (d, J=12 Hz), 137.4 (d, J=11.3 Hz), 134.2 (d, J=20.3 Hz), 129.1 s, 128.1 (d, J=7.5 Hz), 77.4 (d, J=11.3 Hz), 75.0 (d, J=26.2 Hz), 74.0 (d, J=22.3 Hz), 72.1 bs, 71.9-71.5 m, 71.1 s, 69.0 s, 27.6 (d, J=10 Hz), 27.55 8d, J=10 Hz), 20.3-19.9 m

(42) .sup.1H (300 MHz, CDCl.sub.3): 7.52-7.44 (m, 4H), 7.33-7.23 (m, 6H), 4.23 (sept, J=1.2 Hz, 1H), 4.1-4.0 (m, 4H), 3.93-3.9 (m, 1H), 3.87-3.84 (m, 1H), 3.58-3.54 (m, 1H),

(43) 2.1-1.9 (m, 2H), 0.99 (d, J=7 Hz, 3H), 0.94 (d, J=7 Hz, 3H), 0.83-0.7 (m, 6H)

Preparation of Compound 22

(44) ##STR00015##

(45) 0.9 g of tert-butylchloro(thiophen-2-yl)phosphine (4.36 mmol) is weighed out under argon together with 5 ml of heptane in a dropping funnel. Into another 25 ml Schlenk vessel under argon is weighed 0.4 g of ferrocene (2.2 mmol), provided with a magnetic stirrer and admixed with 3 ml of absolute heptane and 0.8 ml of absolute TMEDA (tetramethylethylenediamine, 0.58 g, 5 mmol). The mixture is heated gently until the ferrocene dissolves completely. Then, at room temperature, 2.9 ml of a 1.6 N butyllithium solution (4.6 mmol) are added to the ferrocene solution. This Schlenk vessel is left to stand at 4? C. in a refrigerator for 48 hours. Large crystals of the dilithium salt of ferrocene are formed (orange-brown colour). The supernatant solution is decanted off from these under argon. And 5 ml of absolute heptane are added. While stirring, the solution containing the chlorophosphine is then added and the suspension is stirred at room temperature for one hour. The large crystals dissolve and a precipitate of lithium chloride formed is observed. Then this solution is washed three times with 5 ml each time of degassed water. The mixture is concentrated to dryness and the residue is taken up in 10 ml of absolute diethyl ether. This solution is filtered with dimethyl ether through 5 cm of G 60 silica gel. The diethyl ether is removed under reduced pressure. This leaves about 1 g of crude product. To this are added 3 ml of MeOH and the mixture is left to stand in the refrigerator at 4? C. overnight. Orange crystals are formed, which are obtained in a non-optimized yield of 500 mg as the target product (45% of theory).

(46) Analysis:

(47) .sup.31P (acetone-d.sub.6, 121 MHz), ?6.9 s, ?7.08 s

(48) .sup.1H (acetone-d6, 300 MHz) 7.76-7.7 m (2H), 7.5-7.4 m (2H), 7.2-7.1 m (2H), 4.3-4.2 m (1.4H), 4.13-4.08 m (0.7H), 3.98-3.75 m, (5H), 0.8 d (J.sub.PH=12.8 Hz), 0.8 d (J.sub.PH=16.1 Hz),

(49) .sup.13C (acetone-d6, 75 MHz), 139.09 s, 138.6 d (J.sub.PC=7 Hz), 132.4 s, 127.8 d (J.sub.PC=10.5 Hz), 78.3 s, 77.8 s, 75.2 s, 73.6-73.3 m, 73.08 s, 72.6 d (J.sub.PC=9.6 Hz), 72.6 d (J.sub.PC=10 Hz), 69.7 s, 31.3 d (J.sub.PC=9.8 Hz), 28.1 d (J.sub.PC=15.3 Hz),

(50) HRMS calculated for C.sub.26H.sub.32Fe.sub.1P.sub.2S.sub.2: 526.07646, found: 526.07647,

(51) MS (EI, 70 eV (Mz/%), 526 (M+, 38), 469(100), 413(94), 329(5), 299(31), 266(6)216(18)171/17)151(4.58), 115 (8)

Preparation of Compound 34

(52) ##STR00016##

(53) In a 100 ml three-neck flask provided with a magnetic stirrer and a low-temperature thermometer, under argon, 0.63 ml (0.547 g, 7.08 mmol) of N-methylpyrrole (freshly distilled from calcium hydride), 20 ml of absolute diethyl ether and 1.2 ml (0.8 g) of TMEDA are mixed while stirring. The mixture is cooled to ?78? C. and, by means of a dropping funnel, 4.35 ml of 1.6 N BuLi solution in hexane (7.2 mmol) are added dropwise within 10 minutes. Then the mixture is warmed to room temperature and stirred at this temperature for half an hour. 1.12 g of tert-butyldichlorophosphine in a 100 ml Schlenk vessel are admixed with 20 ml of absolute diethyl ether under magnetic stirring, and cooled down to ?78? C. At this temperature, the first solution consisting of Et.sub.2O/TMEDA/lithiated N-methylpyrrole is added to the solution of the chlorophosphine while stirring. In a further 100 ml Schlenk vessel, 0.65 g (3.5 mmol) of ferrocene is dissolved in 10 ml of heptane under argon, and 1.2 ml of TMEDA (7.1 mmol) and 4.3 ml of 1.6 N butyllithium solution are added (7.1 mmol). This solution is left to stand at 4? C. in the refrigerator overnight. Large orange crystals are formed. The supernatant solution is decanted off and 20 ml of heptane are added to the crystals. Then the solution consisting of the N-methylimidazolylchlorophosphine is added to this stirred suspension at room temperature by means of a capillary. This suspension is stirred at room temperature for one hour. Then it is washed three times with 20 ml of degassed water. Subsequently, the mixture is concentrated to dryness under reduced pressure, and the oily residue is taken up in 20 ml of absolute toluene and columned under argon with toluene as diluent through silica gel 60. Yield of 25% (450 mg).

(54) Analytical Data

(55) Purity (NMR)(100%)

(56) .sup.31P NMR (CDCl.sub.2, 121 MHz)=?27.41 s, ?27.52 s

(57) .sup.13C NMR (CDCl.sub.2, 75 MHz)=127.02 s, 125.34 s, 118.5 s, 108.11 s, 78.6 d, J.sub.PC=42 Hz, 75.0 s, 72.7 d, J.sub.PC=6.3 Hz, 71.9 s, 71.4 d, J.sub.PC=11.5 Hz, 66.0 s, 36.2 d, J.sub.PC=21.9 Hz, 31.0 d, J.sub.PC=6.3 Hz, 27.75 d, J.sub.PC=15.8 Hz,

(58) .sup.1H NMR (CDCl.sub.2, 300 MHz): 6.82-6.7 m (2H), 6.5, d,d J=1.5 Hz, J=3.7 Hz, 6.45 d,d J=1.6, J=3.7 Hz (2H), 6.18 d,d, J=2.5 Hz J=3.7 Hz, 4.2 m, 4.1-3.9 m, 3.9 s, 3.8 s, 3.8-3.74 m, 0.8 d, J=13.2 Hz

(59) HRMS calculated for C.sub.28H.sub.38FeN.sub.2P.sub.2: 520.18545, found: 520.18643.

(60) High-Pressure Experiments

(61) Feedstocks:

(62) Methanol (MeOH)

(63) Ethene (also referred to as ethylene)

(64) Di-n-butene was also referred to as follows: dibutene, DNB or DnB.

(65) Di-n-butene is an isomer mixture of C8 olefins which arises from the dimerization of mixtures of 1-butene, cis-2-butene and trans-2-butene. In industry, raffinate II or raffinate III streams are generally subjected to a catalytic oligomerization, wherein the butanes present (n/iso) emerge unchanged and the olefins present are converted fully or partly. As well as dimeric di-n-butene, higher oligomers (tributene C12, tetrabutene C16) generally also form, which have to be removed by distillation after the reaction.

(66) One process practised in industry for oligomerization of C4 olefins is called the OCTOL process.

(67) Within the patent literature, DE102008007081A1, for example, describes an oligomerization based on the OCTOL process. EP1029839A1 is concerned with the fractionation of the C8 olefins formed in the OCTOL process.

(68) Technical di-n-butene consists generally to an extent of 5% to 30% of n-octenes, 45% to 75% of 3-methylheptenes, and to an extent of 10% to 35% of 3,4-dimethylhexenes. Preferred streams contain 10% to 20% n-octenes, 55% to 65% 3-methylheptenes, and 15% to 25% 3,4-dimethylhexenes.

(69) para-Toluenesulphonic acid was abbreviated as follows: pTSA, PTSA or p-TSA.

(70) PTSA in this text always refers to para-toluenesulphonic acid monohydrate.

(71) General Method for Performance of the High-Pressure Experiments:

(72) General Experiment Description for Reactions in Batchwise Mode:

(73) The appropriate amounts of substrate, palladium salt, acid and alcohol are mixed under argon in a 50 ml Schlenk vessel while stirring with a magnetic stirrer.

(74) A 100 ml steel autoclave from Parr provided with a gas inlet and a gas outlet valve, a digital pressure transducer, a temperature sensor and a ball valve, and an installed capillary for sampling, is freed of oxygen by means of vacuum and argon purging three times. Subsequently, the reaction solution from the Schlenk flask is introduced by means of a capillary into the autoclave in an argon counterflow through the ball valve. Subsequently, either the appropriate amount of CO is injected at room temperature and then the autoclave is heated up to reaction temperature (reactions that are not run under constant pressure) or the autoclave is first heated up to reaction temperature and then the CO is injected by means of a burette connected to the autoclave by means of a pressure reducer. This burette is then filled with CO to about 100 bar and, during the reaction, supplies the CO required at a constant pressure. This burette has a dead volume of about 30 ml and is provided with a digital pressure transducer. Then the reaction is conducted at the required temperature for the required time while stirring. In the course of this, by means of software (Specview from SpecView Corporation) and a Parr 4870 process controller and a 4875 power controller, data for the pressure variation in the autoclave and in the gas burette are recorded. If required, via the capillary, the GC samples are collected and analysed. For this purpose, a suitable exact amount (2-10 ml) of isooctane as internal standard is also added to the Schlenk vessel. These also give information about the course of the reaction. At the end of the reaction, the autoclave is cooled down to room temperature, the pressure is cautiously released, isooctane is added if necessary as internal standard, and a GC analysis or, in the case of new products, a GC-MS analysis is conducted as well.

(75) General Method for Experiments in the 12-Vial Autoclaves (600 ml Parr Autoclave):

(76) Baked-out glass vials are each initially charged with di-n-butene (DNB) and methanol, and a solution of Pd(acac).sub.2 (0.5 mg, 0.0016 mmol) and ligand (0.0064 mmol) in 0.2 ml of methanol is added, as is H.sub.2SO.sub.4 (solution: 1 ml of H.sub.2SO.sub.4 in 50 ml MeOH). In the autoclave, the mixtures are purged twice with 10 bar of CO, CO is injected to the desired pressure, and the mixtures are stirred at the desired temperature for 20 h. After the reaction has ended, isooctane (internal standard) and 1 ml of EtOAc are added in each case. The organic phase is analysed by GC.

(77) The yields of the reactions are determined by means of GC (isooctane as internal standard).

(78) Analysis:

(79) GC analysis of the products from ethene: For the GC analysis, an Agilent 7890A gas chromatograph having a 30 m HP column is used. Temperature profile: 35? C., 10 min; 10? C./min to 200? C., 16.5 min; the injection volume is 1 ?l with a split of 50:1. Retention time of methyl propionate: 6.158 min

(80) GC analysis of di-n-butene: For the GC analysis, an Agilent 7890A gas chromatograph having a 30 m HP5 column is used. Temperature profile: 35? C., 10 min; 10? C./min to 200? C.; the injection volume is 1 ?l with a split of 50:1.

(81) Retention times for di-n-butene and products: 10.784-13.502 min

(82) The esters formed from di-n-butene are referred to hereinafter as MINO (methyl isononanoate).

(83) Retention times for ether products of unknown isomer distribution: 15.312, 17.042, 17.244, 17.417 min

(84) Retention time for iso-C9 esters 19.502-20.439 min (main peak: 19.990 min)

(85) Retention time for n-C9 esters: 20.669, 20.730, 20.884, 21.266 min.

(86) Methanol Analysis

(87) Methanol was pretreated in a solvent drying system: PureSolv MD Solvent Purification System, from Innovative Technology Inc. One Industrial Way, Amesbury Mass. 01013

(88) Water Values:

(89) Determined by Karl Fischer titration: TitraLab 580-TIM580, from Radiometer Analytical SAS (Karl Fischer titration), water content: measurement ranges, 0.1%-100% w/w, measured water content: 0.13889%

(90) The following were used:

(91) Technical grade methanol from Applichem: No. A2954,5000, batch number: LOT: 3L005446 water content max. 1%

(92) Methanol from Acros Organics (over molecular sieve): water content 0.005%, code number: 364390010, batch number: LOT 1370321

(93) TON: turnover number, defined as moles of product per mole of catalyst metal

(94) TOF: turnover frequency, defined as TON per unit time for the attainment of a particular conversion, e.g. 50%.

(95) The n/iso ratio indicates the ratio of olefins converted terminally to esters to olefins converted internally to esters.

(96) The n selectivities reported hereinafter relate to the proportion of terminal methoxycarbonylation based on the overall yield of methoxycarbonylation products.

(97) Methoxycarbonylation of Ethene with Ligand 22

(98) ##STR00017##

(99) A 100 ml steel autoclave is charged with Pd(acac).sub.2 (6.52 mg, 0.04 mol %) and ligand 22 (45.5 mg, 0.16 mol %) and PTSA (61.1 mg, 0.6 mol %) and methanol (20 ml) under argon. Then 1.5 g (53.6 mmol) of ethene (3.5 from Linde AG) are transferred into the autoclave (monitoring by mass of the autoclave). After heating to a reaction temperature of 80? C. (pressure about 10 bar), CO (30 bar) is injected at this temperature. The reaction is conducted at this temperature for 20 hours. Then the autoclave is cooled down to room temperature and decompressed. The contents are transferred to a 50 ml Schlenk vessel, and isooctane (internal standard, 5.0 ml) is added. The yield and selectivity were determined by means of GC analysis (yield: 91%).

(100) Methoxycarbonylation of Ethene with Ligand 59 (Comparative Experiment)

(101) ##STR00018##
Ligand 59:

(102) Ligand 59, 1,1-bis(diphenylphosphino)ferrocene, is commercially available.

(103) A 100 ml steel autoclave is charged with Pd(acac).sub.2 (6.52 mg, 0.04 mol %) and ligand 59 (47.9 mg, 0.16 mol %) and PTSA (61.1 mg, 0.6 mol %) and methanol (20 ml) under argon. Then 1.5 g (53.6 mmol) of ethylene (3.5 from Linde AG) are transferred into the autoclave. (Monitoring the mass of the autoclave). After the autoclave has been heated up to a reaction temperature of 80? C. (pressure about 10 bar), CO (30 bar) is injected at this temperature. At this temperature, the reaction is conducted for 20 hours. Then the autoclave is cooled down to room temperature and decompressed. The contents are transferred into a 50 ml Schlenk flask, and isooctane (internal standard, 5.0 ml) is added. The yield and selectivity were determined by means of GC analysis. (Yield: 54%).

(104) Methoxycarbonylation of Di-n-Butene with Ligand 16

(105) ##STR00019##

(106) A 100 ml steel autoclave is charged under argon with Pd(acac).sub.2 (5.85 mg, 0.04 mol %), 16 (38 mg, 0.16 mol %), MeOH (20 ml), 7.54 ml of di-n-butene (48 mmol) und PTSA (54.7 mg, 0.6 mol %). Then CO is injected into the autoclave to 40 bar at room temperature. The reaction is conducted at 120? C. 20 hours. After the reaction, the autoclave is cooled down to room temperature and the pressure is released. 5 ml of isooctane are added to the solution as an internal standard. The yield and selectivity were determined by means of GC analysis (yield: 30%, n/iso: 79:21).

(107) Methoxycarbonylation of Di-n-Butene with Ligands 10 and 19 (Comparative Experiments in a 12-Well Autoclave)

(108) The conversion of di-n-butene with the aid of various ligands was effected by the following method:

(109) A 50 ml Schlenk vessel was charged with [Pd(acac).sub.2] (3.9 mg, 0.04 mol %), MeSO.sub.3H (methanesulphonic acid) (13 ?l, 0.6 mol %) and MeOH (20 ml). A 4 ml vial was charged with ligand X (0.16 mol %), and a magnetic stirrer bar was added. Thereafter, 1.25 ml of the clear yellow solution and di-n-butene (315 ?l, 2 mmol) were added with a syringe. The vial was placed into a sample holder which was in turn inserted into a 600 ml Parr autoclave under an argon atmosphere. After the autoclave had been purged three times with nitrogen, the CO pressure was adjusted to 40 bar. The reaction proceeded at 120? C. for 20 hours. On conclusion of the reaction, the autoclave was cooled down to room temperature and cautiously decompressed. Isooctane was added as internal GC standard. Yield and regioselectivity were determined by means of GC.

(110) The results are summarized in Scheme 11 below:

(111) ##STR00020##

(112) The experiments described show that the compounds according to the invention are suitable as catalyst ligands for the alkoxycarbonylation of a multitude of ethylenically unsaturated compounds, especially ethene and di-n-butene. More particularly, with the compounds according to the invention, better yields are achieved than with the bidentate phosphine ligands known from the prior art, such as 1,1-bis(diphenylphosphino)ferrocene (ligand 59), 1-(diphenylphosphino)-1-(diisopropylphosphino)ferrocene (ligand 10) and 1,1-bis(isopropylphenylphosphino)ferrocene (ligand 19). In addition, the compounds according to the invention also enable the alkoxycarbonylation of long-chain olefins of industrial importance, such as di-n-butene.