Method for Preparation of a Ruthenium Indenylidene Complex

Abstract

The present invention is directed to a method for the preparation of ruthenium catalyst (PCy 3 ) 2 Cl 2 Ru(phenylindenylidene) (Umicore catalyst “M1”). The method comprises a one-step reaction reacting the precursor compound (PPh 3 ) 2 Cl 2 Ru(3-phenylindenylidene) with PCy 3 in a cyclic ether solvent (preferably THF) in concentrations in the range of 0.2 to 0.6 mol catalyst/l while simultaneously precipitating the product from the reaction mixture. A cyclic ether solvate product with high crystallinity and high purity is obtained.

1 . A method for preparation of the ruthenium-indenylidene carbene catalyst of Formula 1, 
       
         
           
           
               
               
           
         
         said method comprising
 reacting (PPh 3 ) 2 Cl 2 Ru(3-phenylindenylidene) with tricyclohexyl-phosphine (PCy 3 ) in a reaction mixture having a concentration in the range of 0.2 to 0.6 mol Ru-catalyst/l in a cyclic ether solvent and 
 precipitating the resulting catalyst of Formula 1 during the reaction. 
 
       
     
     
         2 . The method according to  claim 1 , wherein the catalyst of Formula 1 precipitates in the form of a crystalline cyclic ether solvate. 
     
     
         3 . The method according to  claim 2 , wherein the cyclic ether solvate comprises >1 molecule of cyclic ether per molecule of catalyst. 
     
     
         4 . The method according to any one of  claims 1  to  3 , wherein the cyclic ether solvent is selected from THF, methyl-THF, dimethyl-THF or mixtures thereof. 
     
     
         5 . The method according to any one of  claims 1  to  4 , wherein the cyclic ether solvent is THF. 
     
     
         6 . The method according to any one of  claims 1  to  5 , wherein the reaction temperature is in the range of 30 to 100° C., preferably in the range of 50 to 80° C. 
     
     
         7 . The method according to any of  claims 1  to  6 , wherein the PCy 3  is present in the range of 2 to 3 equivalents, preferably in the range of 2.1 to 2.5 equivalents. 
     
     
         8 . The method according to any of  claims 1  to  7 , wherein the cyclic ether solvent may be partially distilled off during the reaction. 
     
     
         9 . The method according to any one of  claims 1  to  8 , further comprising a cooling step, wherein the reaction mixture is cooled down to a temperature in the range of −30 to 25° C., preferably in the range of 0 to 25° C. 
     
     
         10 . The method according to any one of  claims 1  to  9 , wherein the reaction time is in the range of 0.1 to 3 hours, preferably in the range of 0.5 to 2 hours. 
     
     
         11 . The method according to any one of  claims 1  to  10 , further comprising steps of separating the resulting ruthenium-indenylidene catalyst from the reaction mixture. 
     
     
         12 . The method according to any one of  claims 1  to  10 , further comprising steps for washing and drying the resulting ruthenium-indenylidene catalyst. 
     
     
         13 . Ruthenium-indenylidene carbene catalyst obtainable by the method according to any one of  claims 1  to  12 , having a purity of >97%, preferably >99% and particularly preferred >99.5% (as determined by  31 P-NMR spectroscopy). 
     
     
         14 . Ruthenium-indenylidene carbene catalyst obtainable by the method according to any one of  claims 1  to  12 , being present in a crystalline cyclic ether solvate form, comprising >1 molecule of cyclic ether per molecule of catalyst (as determined by  1 H-NMR and X-ray analysis). 
     
     
         15 . Ruthenium-indenylidene carbene catalyst obtainable by the method according to  claim 5 , being present in a crystalline THF solvate form, comprising between 1 and 2 molecules of THF per molecule of catalyst (as determined by  1 H-NMR and X-ray analysis). 
     
     
         16 . Ruthenium-indenylidene carbene catalyst of Formula 1, 
       
         
           
           
               
               
           
         
       
       being present in a crystalline THF solvate form and showing peaks at diffraction angles (2θ°) in XRD powder diffractometry (Cu—X-ray tube, tube excitation 40 kV, 40 mA) as listed in the following table: 
       
         
           
                 
                 
                 
               
                     
                     
                 
                     
                   Peak No. 
                   diffraction angle (2θ°) 
                 
                     
                     
                 
                     
                   a 
                   about 7.3 
                 
                     
                   b 
                   about 8.7 
                 
                     
                   c 
                   about 9.8 
                 
                     
                   d 
                   about 11.8 
                 
                     
                   e 
                   about 14.2 
                 
                     
                   f 
                   about 14.6 
                 
                     
                   g 
                   about 17.3 
                 
                     
                   h 
                   about 17.9 
                 
                     
                   i 
                   about 18.8 
                 
                     
                   j 
                   about 20.3