Separation of phenol isomer

Abstract

The present subject matter relates to a process for separating compound (I) from a mixture comprising compound (I). The present subject matter also relates to a process for separating compound (I) from a mixture comprising compound (I) and compound (II).

What is claimed is: 
     
         1 . A process for separating compound (I), or a salt thereof, from a mixture comprising the compound (I), 
       
         
           
           
               
               
           
         
         the process comprising the steps of: 
         (a) combining the mixture with an amount of a base in the presence of at least one solvent so as to form a precipitate; and 
         (b) separating the precipitate, 
         thereby separating the compound (I) from the mixture. 
       
     
     
         2 . The process of  claim 1 , wherein the mixture further comprises compound (II) 
       
         
           
           
               
               
           
         
       
     
     
         3 . The process of  claim 2 , wherein the ratio of compound (I) to compound (II) in the mixture is from 1:1000 to 1000:1. 
     
     
         4 . The process of  claim 3 , wherein the ratio of compound (I) to compound (II) in the mixture is from 90:10 to 70:30. 
     
     
         5 . The process of  claim 4 , wherein the ratio of compound (I) to compound (II) in the mixture is 88:11. 
     
     
         6 . The process of any one of  claims 1 - 5 , wherein the base is an organic base or an inorganic base. 
     
     
         7 . The process of  claim 6 , wherein:
 a. the organic base is triethylamine, trimethylamine, ammonia, ammonium hydroxide, pyridine, guanidines, tetramethylammonium hydroxide, tetrabutylammonium hydroxide, choline hydroxide, 1,4-diazabicyclo[2.2.2]octane (DABCO), or   b. the inorganic base is an alkali metal base, hydroxy base, alkoxy base or carbonate base.   
     
     
         8 . The process of  claim 7 , wherein:
 a. the alkali metal base is a sodium base, lithium base, potassium base, magnesium base or calcium base,   b. the alkoxy base is a methoxy base or an ethoxy base, or   c. the carbonate base is lithium carbonate, sodium carbonate, sodium bicarbonate, potassium carbonate or potassium bicarbonate.   
     
     
         9 . The process of any one of  claims 1 - 8 , wherein the base contains water. 
     
     
         10 . The process of any one of  claims 1 - 9 , wherein the mixture reacts with the base in the presence of at least two solvents. 
     
     
         11 . The process of any one of  claims 1 - 10 , wherein at least one of the solvents is a polar solvent selected from alcohol, dimethyl sulfoxide (DMSO), dimethylformamide (DMF), N-Methyl-2-pyrrolidone (NMP), glycols, sulfolan, mono and di-glymes, acetamide, glycerine, acetonitrile (ACN), nitro ethane, and any combination thereof. 
     
     
         12 . The process of  claim 11 , wherein the alcohol is methanol, ethanol or propanol. 
     
     
         13 . The process of any one of  claims 1 - 12 , wherein at least one of the solvents is a nonpolar solvent selected from toluene, xylene, mono chloro benzene (MCB), naphtha, pentane, hexane, or dichloromethane (DCM) and any combination thereof. 
     
     
         14 . The process of any one of  claims 1 - 13 , wherein the mixture is an aqueous solution and the concentration of water in the aqueous solution is not more than 25%. 
     
     
         15 . The process of any one of  claims 1 - 14 , wherein:
 a. the mixture reacts with the base in the presence of one solvent and the solvent is ethanol,   b. the mixture reacts with the base in the presence of two solvents and the solvents are toluene and ethanol, or   c. wherein the mixture reacts with the base in the presence of three solvents and the solvents are toluene, ethanol and water.   
     
     
         16 . The process of any one of  claims 1 - 15 , wherein step a) of the process is performed at a temperature below 50° C. 
     
     
         17 . The process of any one of  claims 1 - 16 , wherein the precipitate is separated in step (b) by filtration, by centrifuge, or by decantation. 
     
     
         18 . The process of any one of  claims 1 - 17 , wherein the precipitate comprises a metal salt of the compound (I). 
     
     
         19 . The process of  claim 18 , wherein:
 a. the precipitate further comprises a metal salt of the compound (II) wherein the ratio of the metal salt of compound (I) to the metal salt of compound (II) in the precipitate is from 50:1 to 1000:1, and/or   b. the purity of the salt of compound (I) in the precipitate is 80% or more, 85% or more, 90% or more, 95% or more, or 99% or more.   
     
     
         20 . The process of  claim 18  or  19 , wherein the process further comprises neutralizing the metal salt of compound (I) with an acid. 
     
     
         21 . The process of  claim 20 , wherein the acid is carboxylic acids, fumaric acid, phthalic acid, maleic acid, malic acid, oxalic acid, adipic acid, glutaric acid, 2-methyl glutaric acid, succinic acid, tartaric acid, tri fluoro methyl acetic acid, p-toluene sulfonic acid, hydrochloric acid, hydrobromidic acid, hydroiodic acid, nitric acid, sulfuric acid, persulfuric acid or any combination thereof. 
     
     
         22 . A method of obtaining a compound (I) 
       
         
           
           
               
               
           
         
         comprising separating the compound (I) according to the process of any one of to  claims 1 - 21 . 
       
     
     
         23 . A compound (I) 
       
         
           
           
               
               
           
         
         or a salt thereof, 
         obtained using the process of any one of  claims 1 - 21 . 
       
     
     
         24 . A compound (I) 
       
         
           
           
               
               
           
         
         or a salt thereof. 
       
     
     
         25 . A composition comprising the compound of  claim 23  or  24 . 
     
     
         26 . A composition comprising a precipitate and at least one solvent, wherein the precipitate comprises a salt of compound (I)