Bicyclo[4.3.0]nonane-3(4),7(8)-dicarboxylic acid and a process for its preparation

1. A process for preparing bicyclo[4.3.0]nonane-3(4),7(8)-dicarboxylic acid by hydroformylating bicyclo[4.3.0]nona-3,7-diene with subsequent oxidation, which comprises reacting bicyclo[4.3.0]nona-3,7-diene with synthesis gas in an homogeneous organic phase in the presence of transition metal compounds of Group VIII of the Periodic Table containing complex-bound organophosphorus compounds, and of excess organophosphorus compound, at temperatures of 70 to 160° C. and pressures of 5 to 35 MPa, and then oxidizing the resulting 3(4),7(8)-bisformylbicyclo[4.3.0]nonane to obtain bicyclo[4.3.0]nonane-3(4),7(8)-dicarboxylic acid.

2. A process for preparing bicyclo[4.3.0]nonane-3(4),7(8)-dicarboxylic acid by hydroformylating bicyclo[4.3.0]nona-3,7-diene with subsequent hydrogenation and subsequent reaction in an alkali melt, which comprises reacting bicyclo[4.3.0]nona-3,7-diene with synthesis gas in an homogeneous organic phase in the presence of transition metal compounds of Group VIII of the Periodic Table containing complex-bound organophosphorus compounds, and of excess organophosphorus compound, at temperatures of 70 to 160° C. and pressures of 5 to 35 MPa, hydrogenating the 3(4),7(8)-bisformylbicyclo[4.3.0]nonane thus obtained to obtain 3(4),7(8)-dihydroxymethylbicyclo[4.3.0]nonane, reacting the 3(4),7(8)-dihydroxymethylbicyclo[4.3.0]nonane thus obtained in an alkali melt at elevated pressure, and then releasing bicyclo[4.3.0]nonane-3(4),7(8)-dicarboxylic acid.

3. The process of claim 1 , wherein the organophosphorus compounds used are organic phosphorus(III) compounds selected from the group consisting of triarylphosphines, alkylarylphosphines, alkyl phosphites, aryl phosphites, alkyl diphosphites and aryl diphosphites.

4. The process of claim 3 , wherein the triarylphosphine used is triphenylphosphine and the aryl phosphite used is tris(2-tert-butylphenyl) phosphite or tris(2-tert-butyl-4-methylphenyl) phosphite.

5. The process of claim 1 , wherein the transition metal compounds of Group VIII of the Periodic Table used are selected from the group consisting of compounds of rhodium, cobalt, iridium, nickel, palladium, platinum, iron and ruthenium.

6. The process of claim 1 , wherein the transition metal compounds of Group VIII of the Periodic Table used are compounds of rhodium.

7. The process of claim 1 , wherein rhodium is used in a concentration of 5 to 1,000 ppm by weight based on the homogeneous reaction mixture.

8. The process of claim 7 , wherein rhodium is used in a concentration of 10 to 700 ppm by weight, based on the homogeneous reaction mixture.

9. The process of claim 1 , wherein the molar ratio of rhodium to phosphorus is 1:5 to 1.200.

10. The process of claim 9 , wherein the molar ratio of rhodium to phosphorus is 1:10 to 1:100.

11. The process of claim 1 , wherein the hydroformylation is performed at temperatures of 80 to 150° C., and at pressures of 10 to 30 MPa.

12. The process of claim 2 , wherein the hydrogenation is performed in the presence of nickel catalysts at temperatures of 70 to 170° C. and at pressures of 1 to 30 MPa.

13. The process of claim 2 , wherein 3(4),7(8)-dihydroxymethylbicyclo[4.3.0]nonane is reacted in an alkali melt at temperatures of 200 to 350° C. and at pressures of 0.5 to 5 MPa.

14. The process of claim 1 , wherein the oxidation of 3(4),7(8)-bisformylbicyclo[4.3.0]nonane is performed at temperatures of 20 to 80° C. and at pressures of standard pressure to 1.0 MPa.

15. The process of claim 14 , wherein the oxidizing agents used are oxygen or air.

16. The bicyclo[4.3.0]nonane-3(4),7(8)-dicarboxylic acid.