Bisphosphines as bidentate ligands

Abstract

The present invention relates to ligands of the general formula (I). In addition, a process for the production thereof and the use thereof are demonstrated.

1 . A ligand represented by formula (I),  
       
         
           
           
               
               
           
         
         wherein R 1 , R 2 , R 3 , and R 4 , are independently selected from the group consisting of (C 1 -C 8 )-alkyl, (C 2 -C 8 )-alkoxyalkyl, (C 6 -C 18 )-aryl, (C 7 -C 19 )-aralkyl, (C 3 -C 18 )-heteroaryl, (C 4 -C 18 )-heteroaralkyl, (C 1 -C 8 )-alkyl-(C 6 -C 18 )-aryl, (C 1 -C 8 )-alkyl-(C 3 -C 18 )-heteroaryl, (C 3 -C 8 )-cycloalkyl, (C 1 -C 8 )-alkyl-(C 3 -C 8 )-cycloalkyl, and (C 3 -C 8 )-cycloalkyl-(C 1 -C 8 )-alkyl, or  
         R 1  and R 2  represent a (C 3 -C 5 )-alkylene bridge mono or polysubstituted with (C 1 -C 8 )-alkyl, HO—(C 1 -C 8 )-alkyl, (C 1 -C 8 )-alkoxy, (C 2 -C 8 )-alkoxyalkyl, (C 6 -C 18 )-aryl, (C 7 -C 18 )-aralkyl, (C 1 -C 8 )-alkyl-(C 6 -C 18 )-aryl, (C 3 -C 8 )-cycloalkyl, (C 1 -C 8 )-alkyl-(C 3 -C 8 )-cycloalkyl or (C 3 -C 8 )-cycloalkyl-(C 1 -C 8 )-alkyl, optionally linked to a polymer enlargement, and  
         R 3  and R 4  represent a (C 3 -C 5 )-alkylene bridge mono or polysubstituted with (C 1 -C 8 )-alkyl, HO—(C 1 -C 8 )-alkyl, (C 1 -C 8 )-alkoxy, (C 2 -C 8 )-alkoxyalkyl, (C 6 -C 18 )-aryl, (C 7 -C 19 )-aralkyl, (C 1 -C 8 )-alkyl-(C 6 -C 18 )-aryl, (C 3 -C 8 )-cycloalkyl, (C 1 -C 8 )-alkyl-(C 3 -C 8 )-cycloalkyl or (C 3 -C 8 )-cycloalkyl-(C 1 -C 8 )-alkyl, optionally linked to a polymer enlargement;  
         A is represented by  
         
           
             
             
                 
                 
             
           
         
         wherein  
         R is selected from the group consisting of H, (C 1 -C 8 )-alkyl, (C 6 -C 18 )-aryl, (C 7 -C 19 )-aralkyl, (C 1 -C 8 )-alkyl-(C 6 -C 18 )-aryl, (C 3 -C 8 )-cycloalkyl, (C 1 -C 8 )-alkyl-(C 3 -C 8 )-cycloalkyl, (C 3 -C 8 )-cycloalkyl-(C 1 -C 8 )-alkyl, and a link to a polymer enlargement; and  
         Q is selected from the group consisting of O, NH and NR.  
       
     
     
         2 . The ligand according to  claim 1 , the ligand is represented by formula (II),  
       
         
           
           
               
               
           
         
         wherein  
         R 5 , R 6 , R 7 , R 8 , R 9 , R 10 , R 11 , R 12  are independently selected from the group consisting of (C 1 -C 8 )-alkyl, HO—(C 1 -C 8 )-alkyl, (C 1 -C 8 )-alkoxy, (C 2 -C 8 )-alkoxyalkyl, (C 6 -C 18 )-aryl, (C 7 -C 18 )-aralkyl, (C 1 -C 8 )-alkyl-(C 6 -C 18 )-aryl, (C 3 -C 8 )-cycloalkyl, (C 1 -C 8 )-alkyl-(C 3 -C 8 )-cycloalkyl, (C 3 -C 8 )-cycloalkyl-(C 1 -C 8 )-alkyl, and a link to a polymer enlargement.  
       
     
     
         3 . The ligand according to  claim 1 , wherein the polymer enlargement is formed by selecting from the group consisting of polyacrylates, polyacrylamides, polyvinylpyrrolidinones, polysiloxanes, polybutadienes, polyisoprenes, polyalkanes, polystyrenes, polyoxazolines, polyethers and mixtures thereof.  
     
     
         4 . The ligand according to  claim 1 , wherein the ligand is bound to the polymer enlargement via a linker selected from the group consisting of 
 a) —Si(R 2 )—   b) —(SiR 2 —O) n — wherein n=1-10000    c) —(CHR—CHR—O) n — wherein n=1-10000    d) —(X) n — wherein n=1-20    e) Z-(X) n — wherein n=0-20    f) —(X) n —W wherein n=0-20 and    g) Z-(X) n —W wherein n=0-20    wherein    R is selected from the group consisting of H, (C 1 -C 8 )-alkyl, (C 6 -C 18 )-aryl, (C 7 -C 19 )-aralkyl, ((C 1 -C 8 )-alkyl) 1-3 -(C 6 -C 18 )-aryl, X denotes (C 6 -C 18 )-arylene, (C 1 -C 8 )-alkylene, (C 1 -C 8 )-alkenylene, ((C 1 -C 8 )-alkyl) 1-3 -(C 6 -C 18 )-arylene, and (C 7 -C 19 )-aralkylene-; and    Z and W are independently selected from the group consisting of —C(═O)O—, —C(═O)NH—, —C(═O)—, NR, O, CHR, CH 2 , C═S, S, and PR.    
     
     
         5 . The ligand according to  claim 1 , wherein the ligand is a homogeneously soluble catalyst.  
     
     
         6 . The ligand according to  claim 5 , wherein the average molecular weight of the catalysts is in the range of 5,000-300,000 g/mol.  
     
     
         7 . The ligand according to  claim 1 , wherein the ligand is represented by formula (III) or (IV)  
       
         
           
           
               
               
           
         
         wherein  
         R′═H or R; and  
         R is independently selected from the group consisting of (C 1 -C 8 )-alkyl, HO—(C 1 -C 8 )-alkyl, (C 2 -C 8 )-alkoxyalkyl, (C 6 -C 18 )-aryl, (C 7 -C 19 )-aralkyl, (C 1 -C 8 )-alkyl-(C 6 -C 18 )-aryl, (C 3 -C 8 )-cycloalkyl, (C 1 -C 8 )-alkyl-(C 3 -C 8 )-cycloalkyl and (C 3 -C 8 )-cycloalkyl-(C 1 -C 8 )-alkyl.  
       
     
     
         8 . The ligand according to  claim 7 , wherein R is selected from the group consisting of methyl, ethyl, propyl, iso-propyl, tert.-butyl and phenyl.  
     
     
         9 . The ligand according to  claim 1 , wherein 
 Q is oxygen or NR′, and    R′ can be is selected from the group consisting of (C 1 -C 8 )-alkyl, (C 6 -C 18 )-aryl and benzyl.    
     
     
         10 . The ligand according to  claim 1 , wherein 
 Q is oxygen or NR′, and    R′ is selected from the group consisting of methyl, ethyl, propyl, iso-propyl, tert.-butyl, phenyl, naphthyl, fluorenyl and benzyl.    
     
     
         11 . The ligand according to  claim 1 , wherein the ligand has an enantiomer enrichment of greater than 90%.  
     
     
         12 . A complex comprising the ligand according to  claim 1  and at least one transition metal.  
     
     
         13 . The complex according to  claim 12 , wherein the at least one transition metal is selected from the group consisting of palladium, platinum, rhodium, ruthenium, osmium, iridium, cobalt, nickel, copper and mixtures thereof.  
     
     
         14 . A process for producing the ligand according to  claim 1 , the process comprising: 
 reacting LiP(SiMe 3 ) 2  with appropriate co-reactants having at least one nucleofuge leaving group in the presence of an organometallic base to obtain a trimethylsilylphosphine    reacting the trimethylphosphine with a dihalogen derivative of the structures represented by A,    wherein the halogen atoms are positioned on the free valencies of the structures represented by A.    
     
     
         15 . (canceled)  
     
     
         16 . A catalyst comprising the complex according to  claim 12 , wherein said catalyst is comprised in at least one asymmetric reaction.  
     
     
         17 . The catalyst according to  claim 16 , wherein said at least one asymmetric reaction is selected from the reaction consisting of hydrogenation, hydroformylation, rearrangement, allylic alkylation, cyclopropanation, hydrosilylation, hydride transfer reactions, hydroborations, hydrocyanations, hydrocarboxylations, aldol reactions, Heck reaction and mixtures thereof.  
     
     
         18 . The catalyst according to  claim 17 , wherein said asymmetric reaction is hydrogenation and/or hydroformylation.  
     
     
         19 . The catalyst according to  claim 18 , wherein said asymmetric reaction is hydrogenation and said hydrogenation comprises hydrogenating an E/Z mixture of prochiral, N-acylated β-aminoacrylic acids or derivatives thereof.  
     
     
         20 . The catalyst according to  claim 17 , wherein said asymmetric reaction is hydrogenation and said hydrogenation is carried out with hydrogen gas or by transfer hydrogenation.  
     
     
         21 . The catalyst according to  claim 20 , wherein said hydrogenation is carried with hydrogen gas and said hydrogenation is carried out at 0.1 to 10 bar of hydrogen pressure.  
     
     
         22 . The catalyst according to  claim 21 , wherein said hydrogenation is carried at temperatures of −20° C. to 100° C.  
     
     
         23 . The catalyst according to  claim 16 , wherein the ratio of a substrate to the catalyst (substrate:catalyst) is between 10000:1 and 10:1.  
     
     
         24 . The catalyst according to  claim 16 , wherein said metric reaction is carried out in a membrane reactor.