Method for synthesizing optically active carbonyl compounds

Abstract

The present invention relates to a process for the preparation of an optically active carbonyl compound by asymmetric hydrogenation of a prochiral α,β-unsaturated carbonyl compound with hydrogen in the presence of at least one optically active transition metal catalyst that is soluble in the reaction mixture and which has rhodium as catalytically active transition metal and a chiral, bidentate bisphosphine ligand, wherein the reaction mixture during the hydrogenation of the prochiral α,β-unsaturated carbonyl compound additionally comprises at least one compound of the general formula (I):in whichR1, R2: are identical or different and are C6- to C10-aryl which is unsubstituted or carries one or more, e.g. 1, 2, 3, 4 or 5, substituents which are selected from C1- to C6-alkyl, C3- to C6-cycloalkyl, C6- to C10-aryl, C1- to C6-alkoxy and amino;Z is a group CHR3R4 or aryl which is unsubstituted or carries one or more, e.g. 1, 2, 3, 4 or 5, substituents which are selected from C1- to C6-alkyl, C3- to C6-cycloalkyl, C6- to C10-aryl, C1- to C6-alkoxy and amino, wherein R3 and R4 are as defined in the claims and the description.

The invention claimed is: 
     
       1. A composition comprising a chiral bidentate bisphosphine ligand and at least one compound of the general formula (I): 
       
         
           
           
               
               
           
         
       
       in which
 R 1  and R 2 : are identical or different and are C 6 - to C 10 -aryl which is unsubstituted or carries one or more substituents which are selected from C 1 - to C 6 -alkyl, C 3 - to C 6 -cycloalkyl, C 6 - to C 10 -aryl, C 1 - to C 6 -alkoxy and amino; 
 Z is a group CHR 3 R 4  or aryl which is unsubstituted or carries one or more substituents which are selected from C 1 - to C 6 -alkyl, C 3 - to C 6 -cycloalkyl, C 6 - to C 10 -aryl, C 1 - to C 6 -alkoxy and amino, in which
 R 3  is C 1 - to C 4 -alkyl, C 1 - to C 4 -alkoxy-C 1 - to C 4 -alkyl, C 3 - to C 6 -cycloalkyl or C 6 - to C 10 -aryl, where one or two nonadjacent CH 2  groups in C 3 - to C 6 -cycloalkyl can also be replaced by an oxygen atom; 
 R 4  is C 1 - to C 4 -alkyl which is unsubstituted or carries a group P(═O)R 4a R 4b , C 1 - to C 4 -alkoxy, C 1 - to C 4 -alkoxy-C 1 - to C 4 -alkyl, C 3 - to C 6 -cycloalkyl or C 6 - to C 10 -aryl, where one or two nonadjacent CH 2  groups in C 3 - to C 6 -cycloalkyl can also be replaced by an oxygen atom, and where C 3 - to C 6 -cycloalkyl and C 6 - to C 10 -aryl are unsubstituted or carry one or more substituents which are selected from C 1 - to C 4 -alkyl, C 1 - to C 4 -alkoxy and amino; 
 or 
 R 3  and R 4 : together with the carbon atom to which they are bonded, are C 4 - to C 8 -cycloalkyl, in which one or two nonadjacent CH 2  groups in C 3 - to C 6  C 4 - to C 8 -cycloalkyl can also be replaced by an oxygen atom and where C 3 - to C 6  C 4 - to C 8 -cycloalkyl is unsubstituted or carries one or more substituents which are selected from C 1 - to C 4 -alkyl, C 1 - to C 4 -alkoxy and A-P(═O)R 4a R 4b ,
 where A is a chemical bond or a C 1 - to C 4 -alkylene; 
 
 and 
 R 4a  and R 4b : are identical or different and are phenyl which is unsubstituted or carries one or more substituents which are selected from C 1 - to C 6 -alkyl, C 3 - to C 6 -cycloalkyl, C 6 - to C 10 -aryl, C 1 - to C 6 -alkoxy and amino. 
 
 
     
     
       2. The composition of  claim 1 , wherein Z in formula (I) is a group CHR 3 R 4 . 
     
     
       3. The composition of claim  2  1, wherein the variables R 1 , R 2 , Z in formula (I) have the following meanings: 
       R 1 , R 2 : are identical or different and are phenyl which is unsubstituted or carries 1, 2 or 3 substituents which are selected from methyl and methoxy; 
       Z is a group CHR 3 R 4 , in which
 R 3  is C 1 - to C 4 -alkyl; 
 R 4  is C 1 - to C 4 -alkyl which is unsubstituted or carries a group P(═O)R 4a R 4b ; 
 or 
 R 3 , R 4 : together with the carbon atom to which they are bonded, is C 3 - C 4 - to C 8 -cycloalkyl in which one or two nonadjacent CH 2  groups can be replaced by one or two oxygen atoms and where C 3 - C 4 - to C 6 -cycloalkyl is unsubstituted or carries a group A-P(═O)R 4a R 4b  and/or has 1, 2, 3 or 4 methyl groups as substituents; where A is a chemical bond, CH 2  or CH(CH 3 ); and 
 R 4a  and R 4b : are identical or different and are C 6 - to C 10 -aryl phenyl which is unsubstituted or carries 1, 2 or 3 substituents which are selected from methyl and methoxy. 
 
     
     
       4. The composition of claim  2  1, in which 
       R 1 , R 2 : are unsubstituted phenyl; 
       R 3  is methyl; 
       R 4  is a group CH(CH 3 )—P(═O)R 4a R 4b  in which R 4a  and R 4b  are in each case unsubstituted phenyl. 
     
     
       5. The composition of  claim 1 , wherein the chiral, bidentate bisphosphine ligand is a compound of the general formulae (IX), (X) or (XI): 
       
         
           
           
               
               
           
         
       
       in which
 R 11 , R 12 : in each case independently of one another are an unbranched, branched or cyclic hydrocarbon radical having 1 to 20 carbon atoms which is saturated or can have one or more, generally 1 to about 4, nonconjugated, ethylenic double bonds and is unsubstituted or carries one or more, generally 1 to 4, identical or different substituents which are selected from OR 19 , NR 20 R 21 , halogen, C 6 -C 10 -aryl and C 3 -C 9 -hetaryl, or 
 R 11  and R 12  together can also be a 2 to 10-membered alkylene group or a 3- to 10-membered cycloalkylene group, in which 1, 2, 3 or 4 nonadjacent CH 2  groups can be replaced by O or N—R 9c , where the alkylene group and the cycloalkylene group are saturated or have one or two nonconjugated ethylenic double bonds, and where the alkylene group and the cycloalkylene group are unsubstituted or carry one or more identical or different substituents which are selected from C 1 - to C 4 -alkyl; 
 R 13 , R 14 : are in each case independently of one another hydrogen or straight-chain or branched C 1 - to C 4 -alkyl and 
 R 15 , R 16 , R 17 , R 18 : are identical or different and are C 6 - to C 10 -aryl which is unsubstituted or carries one or more substituents which are selected from C 1 - to C 6 -alkyl, C 3 - to C 6 -cycloalkyl, C 6 - to C 10 -aryl, C 1 - to C 6 -alkoxy and amino; 
 R 19 , R 20 , R 21 : are in each case independently of one another hydrogen, C 1 -C 4 -alkyl, C 6 -C 10 -aryl, C 7 -C 12 -aralkyl or C 7 -C 12 -alkylaryl, where 
 R 20 , R 21 : can together also be an alkylene chain having 2 to 5 carbon atoms, which can be interrupted by N or O. 
 
     
     
       6. The composition of  claim 5 , wherein the chiral, bidentate bisphosphine ligand is a compound of the general formula (IX). 
     
     
       7. The composition of  claim 6 , wherein the chiral, bidentate bisphosphine ligand is either the compound of the formula (IXa) or the formula (IXb): 
       
         
           
           
               
               
           
         
       
       in which Ph is phenyl. 
     
     
       8. The composition of  claim 6 , wherein the chiral, bidentate bisphosphine ligand is either the compound of the formula (IXc) or the formula (IXd): 
       
         
           
           
               
               
           
         
       
       in which Ph is phenyl. 
     
     
       9. The composition of  claim 1 , where the compound of formula (I) is (2-(diphenylphosphoryl)-1-methylpropyl))diphenylphosphane. 
     
     
       10. The composition of  claim 1 , where the compound of formula (I) is one of the compounds of formulae (I-1a) or (I-1b) or the racemate thereof 
       
         
           
           
               
               
           
         
       
       in which Ph is phenyl, and the racemate thereof. 
     
     
       11. The composition of  claim 6 , where the compound of formula (I) is (2-(diphenylphosphoryl)-1-methylpropyl))diphenylphosphane. 
     
     
       12. The composition of  claim 6 , where the compound of formula (I) is one of the compounds of formulae (I-1a) or (I-1b) or the racemate thereof 
       
         
           
           
               
               
           
         
       
       in which Ph is phenyl, and the racemate thereof. 
     
     
       13. The composition of claim  11  1, further comprising a transition metal compound, which contains rhodium as transition metal. 
     
     
       14. The composition of claim  1  6, further comprising a transition metal compound, which contains rhodium as transition metal. 
     
     
       15. The composition of claim 8, further comprising a transition metal compound, which contains rhodium as transition metal. 
     
     
       16. The composition of claim 5, wherein
 R 11 , R 12 : in each case independently of one another are an unbranched, branched or cyclic hydrocarbon radical having 1 to 20 carbon atoms which is saturated or can have 1 to about 4 nonconjugated, ethylenic double bonds and is unsubstituted or carries 1 to 4 identical or different substituents which are selected from OR 19 , NR 20 R 21 , halogen, C 6 -C 10 -aryl and C 3 -C 9 -hetaryl.