Process for the condensation of a carbonyl compound with an aromatic derivative in a basic medium

Abstract

The invention concerns a condensation method for at least a carbonyl compound bearing at least an electroattractive group on an aromatic derivative bearing at least a hydroxyl function, characterised in that the electroattractive group present on the carbonyl compound is selected among fluoroalkyl derivatives, esters including orthoesters and nitriles and said condensation is carried out in a basic medium.

1 . A process for condensing at least one carbonyl compound carrying at least one electron-withdrawing group with an aromatic derivative carrying at least one hydroxyl functional group, wherein the electron-withdrawing group present on the carbonyl compound is selected from fluoroalkyl derivatives, esters, including orthoesters, and nitriles and said condensation is carried out in a basic medium.  
     
     
         2 . The process as claimed in  claim 1 , wherein the electron-withdrawing group present on the carbonyl compound has a σ p  at least equal to 0.30.  
     
     
         3 . The process as claimed in  claim 1 , wherein the electron-withdrawing group present on the carbonyl compound has a σ p  is greater than or equal to 0.40 and less than 0.75.  
     
     
         4 . The process as claimed in  claim 1 , wherein the electron-withdrawing group present on the carbonyl compound is a polyfluoroalkyl derivative.  
     
     
         5 . The process as claimed in  claim 1 , wherein the electron-withdrawing group present on the carbonyl compound is a polyfluoroalkyl derivative of formula:  
       —(CX 2 ) p -EWG 
       in which 
 the X units, which are identical or different, are a hydrogen atom, a halogen atom or a radical of formula C n X 2n+1  with n being an integer at most equal to 5;  
 p is an integer at most equal to 2;  
 the symbol EWG is an electron-withdrawing group, the possible functional groups of which are inert under the reaction conditions, advantageously a fluorine atom or a perfluorinated residue of formula C n′ X 2n′+1  with n′ being an integer at most equal to 8, advantageously to 5, with the proviso that at least one of the X or EWG units present on the carbon α to the carbonyl functional group is a fluorine atom,  
 and with the total number of carbon atoms of the polyfluoroalkyl derivative between 1 and 15.  
 
     
     
         6 . The process as claimed in  claim 1 , wherein the carbonyl compound additionally carries at its carbonyl functional group either a hydrogen atom or a group selected from C 5  to C 18  aryls, linear or branched C 1  to C 13  alkyls or linear or branched C 2  to C 14  alkenyls, optionally substituted.  
     
     
         7 . The process as claimed in  claim 1 , wherein the carbonyl compound is trifluoroacetaldehyde in its hydrated or anhydrous form.  
     
     
         8 . The process as claimed in  claim 1 , wherein the aromatic derivative corresponds to the general formula I  
       
         
           
           
               
               
           
         
       
       in which: 
 X 1 , X 2  and X 3  are, independently of one another: 
 a heteroatom and preferably a nitrogen atom, or  
 C(R′″), with R′″ being as defined below, and  
 
 R, R″ and R′″ are, independently of one another, a hydrogen atom or an electron-donating substituent or R′ and R″ form, together with the carbon atoms which carry them, a preferably aromatic C 6  hydrocarbonaceous ring comprising, if appropriate, one or more heteroatoms,  
 with at least one of the R′, R″ and R′″ groups being a hydrogen atom.  
 
     
     
         9 . The process as claimed in  claim 1 , wherein the aromatic compound corresponds to the general formula IA  
       
         
           
           
               
               
           
         
       
       in which: 
 X 4  is a nitrogen atom or C(R 2 ) and  
 R 1 , R 2 , R 3 , R 4  and R 5 , which are identical or different, are a hydrogen or halogen atom or a group selected from: C 1  to C 10  alkyls, these being linear or branched, C 1  to C 10  alkoxys, C 1  to C 10  alkyl ethers, amino, mono- or dialkylaminos, or C 3  to C 9  cycloalkyls or heterocycloalkyls, themselves optionally substituted by a halogen atom or a hydroxyl, amino or mono- or dialkylamino group,  
 or either R 1  and R 2  or R 2  and R 3  constitute, with the bond established between them, an aromatic or heteroaromatic ring,  
 with at least one of the R 1 , R 2 , R 3 , R 4  and R 5  substituents being a hydrogen atom.  
 
     
     
         10 . The process as claimed in  claim 1 , wherein the aromatic derivative is a derivative of phenol, 3-hydroxypyridine, naphthol, hydroxyquinoline or hydroxyisoquinoline type.  
     
     
         11 . The process as claimed in  claim 1 , wherein the molar ratio between carbonyl compound and the aromatic (carbonyl compound/aromatic) is at most 1/2 and preferably of at most 1/4 equivalents of aromatic value.  
     
     
         12 . The process as claimed in  claim 1 , wherein the condensation is carried out in the presence of a stoechiometrical deficiency of carbonyl compound.  
     
     
         13 . The process as claimed in  claim 1 , wherein the condensation employs the carbonyl derivative in a ratio of 0,25 to 1 and preferably of 0,25 to 0,5 equivalents of the aromatic derivative.  
     
     
         14 . The process as claimed in  claim 1 , wherein the condensation is carried out in the presence of a stoechiometrical excess of carbonyl compound.  
     
     
         15 . The process as claimed in  claim 1 , wherein the condensation employs the carbonyl derivative in a ratio of at most 1 to 2 and preferably of at most 1 to 1,25 equivalents of the aromatic derivative.  
     
     
         16 . The process as claimed in  claim 1 , wherein the condensation is carried out in the presence of a water-soluble inorganic base.  
     
     
         17 . The process as claimed in  claim 1 , wherein the condensation is carried out in the presence of a water-soluble inorganic base which differs by at least one pK a  unit from the anionic form of the aromatic derivative.  
     
     
         18 . The process as claimed in  claim 1 , wherein the condensation is carried out in the presence of a water-soluble alkali metal salt of hydroxide and carbonate type.  
     
     
         19 . The process as claimed in  claim 1 , wherein the condensation is carried out in the presence of a water-soluble inorganic base which is employed in a proportion of at least one equivalent with respect to the aromatic derivative.  
     
     
         20 . The process as claimed in  claim 1 , wherein the condensation is carried out in the presence of a sodium hydroxide.  
     
     
         21 . The process as claimed in  claim 1 , wherein the condensation is carried out by gradual introduction of the carbonyl compound into the mixture composed of the aromatic derivative and of a water-soluble base.  
     
     
         22 . The process as claimed in  claim 1 , wherein the condensation is carried out in the presence of a basic heterogeneous catalyst.  
     
     
         23 . The process as claimed in  claim 1 , wherein the condensation is carried out in the presence of a basic heterogeneous catalyst which is based on hydroxides and/or oxides of metal salts.  
     
     
         24 . The process as claimed in  claim 1 , wherein the condensation is carried out in the presence of a basic heterogeneous catalyst selected from oxides, hydroxides and basic salts of alkaline earth metals and/or rare earth metals not exhibiting a degree of valency of IV and from the minerals comprising them.  
     
     
         25 . The process as claimed in  claim 1 , wherein the condensation is carried out in the presence of a magnesia as heterogeneous catalyst.  
     
     
         26 . The process as claimed in  claim 1 , wherein the condensation is carried out in the presence of a basic heterogeneous catalyst which is a natural hydrotalcite or a synthetic analogue.  
     
     
         27 . The process as claimed in  claim 1 , wherein the condensation is carried out in the presence of a basic heterogeneous catalyst which is an ytterbium or lanthanum oxide or carbonate.  
     
     
         28 . The process as claimed in  claim 1 , wherein the condensation is carried out in the presence of a basic heterogeneous catalyst which is present in a proportion of 10 to 50% by weight with respect to the aromatic derivative.  
     
     
         29 . The process as claimed in  claim 1 , wherein the condensation is carried out by introducing a basic heterogeneous catalyst into a mixture of the aromatic derivative and of the carbonyl compound.  
     
     
         30 . The process as claimed in  claim 1 , wherein the condensation is carried out by introducing a basic heterogeneous catalyst into a mixture of the aromatic derivative and of the carbonyl compound and by heating the reaction medium at a temperature of greater than or equal to 50° C.  
     
     
         31 . The process as claimed in  claim 1 , wherein the product or products resulting from the condensation of at least one carbonyl compound with the aromatic derivative are recovered by extracting, after neutralizing the reaction medium, or filtering, without neutralizing, when a basic heterogeneous catalyst is employed.  
     
     
         32 . The compound obtained by employing the process as claimed in  claim 1 .  
     
     
         33 . The compound, characterized in that it is of formula II:  
       
         
           
           
               
               
           
         
       
       in which: 
 X 4  is a nitrogen atom or C(R 2 ) and  
 R′ 1 , R′ 2 , R′ 3 , R′ 4  and R′ 5 , which are identical or different, are a hydrogen or halogen atom or a group selected from: C 1  to C 10  alkyls, these being linear or branched, C 1  to C 10  alkoxys, C 1  to C 10  alkyl ethers, amino, mono- or dialkylaminos, or C 3  to C 9  cycloalkyls or heterocycloalkyls, themselves optionally substituted by a halogen atom or a hydroxyl, amino or mono- or dialkylamino group,  
 or either R′ 1  and R′ 2  or R′ 2  and R′ 3  constitute, with the bond established between them, an aromatic or heteroaromatic ring,  
 with at least two of the R′ 1 , R′ 3  and R′ 5  substituents being a group of formula III:  
                     
 in which  
 the X units, which are identical or different, are a hydrogen atom, a halogen atom, preferably fluorine, or a radical of formula C n X 2n+1  with n being an integer at most equal to 5, preferably to 2;  
 p is an integer at most equal to 2;  
 the X′ unit is a hydrogen atom or a group selected from C 5  to C 18  aryls, linear or branched C 1  to C 13  alkyls or linear or branched C 2  to C 14  alkenyls, if appropriate substituted. The substituents can in particular be a hydroxyl group, a halogen atom, a C 1 -C 11  alkyl group and/or a amino group;  
 with the possibility that the X′ unit be bonded to one CX 2  to form a C 4  to C 8  ring;  
 the symbol EWG is an electron-withdrawing group advantageously a fluorine atom or a perfluorinated residue of formula C n′ X 2n′+1  with n′ being a integer at most equal to 8, with the proviso that at least one of the X or EWG units present on the carbon α to the hydroxy functional group is a fluorine atom, and with the total number of carbon atoms of the polyfluoroalkyl derivative of formula III between 1 and 15, preferably between 1 and 10.  
 
     
     
         34 . Compound according to  claim 33 , wherein the preferred value for X′ is hydrogen.  
     
     
         35 . Compound according to  claim 33 , wherein —X 4  is —C(R 2 )═ with R 2  advantageously being hydrogen.  
     
     
         36 . Compound according to  claim 33 , wherein it contains two groups of formula III.  
     
     
         37 . Compound according to  claim 33 , wherein it contains two groups of formula III in positions ortho.  
     
     
         38 . Compound according to  claim 33 , wherein the group of formula III is —CHOH—CF 3 .  
     
     
         39 . Compound according to  claim 33 , characterized in that it is: 
 2,6-bis[2,2,2-trifluoro-1-hydroxyethyl]4-methyl-phenol;    2,2,2-trifluoro-1-(2-hydroxyphenyl)ethanol,    2,2,2-trifluoro-1-(2-hydroxy-5-methylphenyl)ethanol,    2,2,2-trifluoro-1-(2-chlorophenyl)ethanol,    2,2-difluoro-1-(2-hydroxyphenyl)ethanol,    2,2-difluoro-1-(4-hydroxyphenyl)ethanol,    2,2,2-trifluoro-4-(3-hydroxypyridinyl)ethanol, and    2,2,2-trifluoro-2-(3-hydroxypyridinyl)ethanol.