Method of producing nitrile compounds

Abstract

The present invention relates to the manufacture of nitrile compounds from unsaturated organic compounds by reaction with hydrogen cyanide. It relates more particularly to the manufacture of nitrile compounds of use in the synthesis of adiponitrile, an important chemical intermediate in the manufacture of major chemical compounds, such as hexamethylenediamine and ε-caprolactam. The invention provides a process for the manufacture of organic compounds comprising at least one nitrile functional group by carrying out a hydrocyanation reaction between hydrogen cyanide and an organic compound comprising at least one ethylenic unsaturation. This reaction is carried out in the presence of a catalytic system comprising a metal element chosen from the group consisting of nickel, platinum and palladium and an organophosphorus ligand, the reaction medium additionally comprising an ionic liquid in the liquid state at least at the temperature at which the hydrocyanation reaction is carried out.

1 - 25 . (Canceled).  
     
     
         26 . A process for the manufacture of organic compounds comprising at least one nitrile functional group by reaction between hydrogen cyanide and an organic compound having at least one ethylenic unsaturation in the presence of a catalyst comprising an element selected from the group consisting of nickel, platinum and palladium and an organophosphorus ligand, said process comprising the step of carrying out said reaction in a reaction medium with the presence of an ionic liquid which comprises at least one cation and at least one anion and which is liquid at least at a temperature at which the reaction is carried out.  
     
     
         27 . The process according to  claim 26 , wherein a solvent of low polarity is further added to the reaction medium in order to form a two-phase system.  
     
     
         28 . The process according to  claim 26 , wherein the organophosphorus ligand has at least one ionizable functional group or one ionic group.  
     
     
         29 . The process according to  claim 26 , wherein the ionic liquid comprises at least one cation selected from the group consisting of the structures tetraalkylammonium, N-alkylimidazolium, N-alkylpyridinium, N-alkylpicolinium, N-alkyltriazolium, N-alkylfluoropyrazolium, N-pyrrolidinium, alkylsulphonium, tetraalkylphosphonium and alkyloxonium.  
     
     
         30 . The process according to  claim 26 , wherein the ionic liquid comprises at least one anion selected from the group consisting of halides, nitrate, phosphate, hydrosulphate, perfluoroalkylsulphonates, bis(perfluoroalkylsulphonyl)amides, bis(fluorosulphonyl)amide, bis(fluorophosphoryl)amide, tris(perfluoroalkylsulphonyl)methides, boron, aluminium, gallium tetrahalides, iron tetrahalides, phosphorus hexahalides, arsenic hexahalides, antimony hexahalides, zinc trihalides, tin trihalides, and copper dihalides.  
     
     
         31 . The process according to claim  5 , wherein the anion is selected from the group consisting of Br − , I − , BF 4   − , PF 6   − , SbF 6   − , AlCl 4   − , ZnCl 3   − , SnCl 3   −  and (CF 3 SO 2 ) 2 N − .  
     
     
         32 . The process according to  claim 29 , wherein the cation is selected from the group consisting of 1,3-dimethylimidazolium, 1-butyl-2,3-dimethylimidazolium, 1-butyl-3-methylimidazolium and 1,2,3-trimethylimidazolium.  
     
     
         33 . The process according to  claim 26 , wherein the ligand is an organophosphorus ligand selected from the group consisting of mono-dendate organophosphites, polydentate organophosphites, organophosphonites, organophosphinites and organophosphines.  
     
     
         34 . The process according to  claim 33 , wherein the organophosphorus ligand comprises at least one ionic group.  
     
     
         35 . The process according to  claim 34 , wherein the ionic group present in the organophosphorus ligands is a sulphonate, phosphonate, phosphinite, carboxylate or sulphinate anion.  
     
     
         36 . The process according to  claim 34 , wherein the ionic group present in the organophosphorus ligands is a guanidinium, ammonium, pyridinium, imidazolium, phosphonium or sulphonium cation.  
     
     
         37 . The process according to  claim 26 , wherein the organophosphorus ligand is selected from the group consisting of tributylphosphine, dimethyl(n-octyl)phosphine, tricyclohexylphosphine, triphenylphosphine, tolylphosphine, tris(p-methoxyphenyl)phosphine, diphenylethylphosphine, dimethylphenylphosphine, 1,4-bis(diphenylphosphino)butane, triethyl phosphite and diphenyl phosphite.  
     
     
         38 . The process according to  claim 34 , wherein the organophosphorus ligand is selected from the group consisting of triphenylphosphine(mono meta sodium sulphate), (5-sodiocarboxyfur-2-yl)diphenylphosphine and (3-sodiosulphinatophenyl)diphenylphosphine.  
     
     
         39 . The process according to  claim 27 , wherein the solvent of low polarity is selected from the group consisting of hexane, heptane, octane, toluene, diethyl ether, diisopropyl ether and methyl isobutyl ether.  
     
     
         40 . The process according to  claim 26 , wherein the metal element of the catalyst is nickel in the 0 or 1 oxidation state.  
     
     
         41 . The process according to  claim 26 , wherein the organic compound presenting at least one ethylenic unsaturation is an olefin or a diolefin having from 3 to 12 carbon atoms.  
     
     
         42 . The process according to  claim 41 , wherein the organic compound presenting at least one ethylenic unsaturation is 1,3-butadiene.  
     
     
         43 . The process according to  claim 26 , wherein the organic compound having at least one ethylenic unsaturation further presents one nitrile functional group.  
     
     
         44 . The process according to  claim 43 , wherein said organic compound is 3-pentenenitrile or 4-pentenenitrile.  
     
     
         45 . The process according to  claim 26 , further comprising the step of isomerizing branched unsaturated nitrile compounds to linear nitrile compounds.  
     
     
         46 . The process according to  claim 45 , wherein the isomerization step is carried out in the absence of hydrogen cyanide.  
     
     
         47 . The process according to  claim 45 , wherein the reaction is carried out in the presence of a Lewis acid.  
     
     
         48 . The process according to  claim 47 , wherein the Lewis acid is a compound of the elements from Groups Ib, IIb, IIIa, IIIb, IVa, IVb, Va, Vb, VIIb, VIIb or VIII of the Periodic Table.  
     
     
         49 . The process according to  claim 48 , wherein said Lewis acid compound is a halide, sulphate, sulphonate, carboxylate, phosphate, halosulphonate, perhaloalkylsulphonate, fluoroalkylsulphonate, perfluoroalkylsulphonate, bis(perfluoroalkylsulphonyl)amide, or tris(perfluoroalkylsulphonyl)methide.  
     
     
         50 . The process according to  claim 47 , wherein the ionic liquid comprises an anion forming the Lewis acid.  
     
     
         51 . The process according to  claim 26 , wherein the temperature of carrying out the reaction is of between 10° C. and 200° C.