Novel Composition Of 7,9-Dodecadienyl-1-Acetate Isomers And Process For Production Thereof

Abstract

The present invention relates to a process for preparing a mixture M1 of enol phosphate isomers devoid of (E,E) isomer and comprising at least 98% of (E,Z) isomer, at least 0.1% of (Z,Z) isomer and at least 0.1% of (Z,E) isomer, comprising bringing a mixture of isomers of said enol phosphate comprising a detectable amount of (E,E) isomer into contact with a hydrolysable dienophile in an organic solvent, followed by base hydrolysis of the medium obtained and elimination of the adduct formed, in order to obtain the mixture M1 devoid of (E,E) isomer.

1 . A process to obtain an isomer mixture M2 of a compound of formula 3. 
       
         
           
           
               
               
           
         
         wherein R 2  is a linear alkyl group comprising 1 to 8 carbon atoms, R 3 , R 4  and R 5  are independently chosen from among H and CH 3 , R 6  represents a linear or branched C 1 -C 6  alkyl group, wherein its isomeric purity is greater than or equal to 98% in (E,Z) isomer and wherein it contains at least 0.1% of (Z,E) and (Z,Z) isomers and less than 1% of (E,E) isomer, comprising the steps of: 
         a) Contacting a mixture of enol phosphate isomers of formula 1 
       
       
         
           
           
               
               
           
         
         wherein R 1  and R′ 1  independently designate an alkyl group comprising 1 to 6 carbon atoms or an aryl group, and R 2 , R 3 , R 4  and R 5  are as defined above, 
         with a hydrolysable dienophile D, 
         wherein the mixture of enol phosphate isomers of formula 1 comprises a detectable quantity of (E,E) isomer, and wherein the detectable quantity is a quantity above 0.1%, 
         b) Basic hydrolysis of the medium obtained in step a) and elimination of the adduct formed to obtain a mixture M1 of enol phosphate isomers of formula 1, free of (E,E) isomer and comprising at least 98% of (E,Z) isomer, at least 0.1% of (Z,Z) isomer and at least 0.1% of (Z,E) isomer, and 
         c) Contacting the mixture M1 of enol phosphate isomers of formula 1 free of (E,E) isomer and comprising at least 98% of isomer (E,Z), at least 0.1% of (Z,Z) isomer and at least 0.1% of (Z,E) isomer obtained at step b) with a compound XMg-R 6 -OMgX, wherein each X independently represents a halogen atom, and RB represents a linear or branched C 1 -C 6  alkyl group, and then contacting the mixture obtained with an acylation agent. 
       
     
     
         2 . The process according to  claim 1 , wherein enol phosphate of formula 1 is a compound of formula 2. 
       
         
           
           
               
               
           
         
         R 1  and R′ 1  having the same meaning as in  claim 1 . 
       
     
     
         3 . The process according to  claim 1 , wherein the step a) is performed at a temperature T equal to 70° C. 
     
     
         4 . The process according to  claim 1 , wherein the hydrolysable dienophile D is maleic anhydride. 
     
     
         5 . The process according to  claim 1 , wherein the step a) is performed in an organic solvent S which is methylcyclohexane. 
     
     
         6 . A mixture M1 of (E,Z), (Z,E), and (Z,Z) enol phosphate isomers of formula 1 as defined in  claim 1 , having an isomeric purity greater than or equal to 98% in (E,Z) isomer and containing at least 0.1% of (Z,E) and (Z,Z) isomers. 
     
     
         7 . The mixture M1 according to  claim 6 , wherein the enol phosphate of formula 1 is diethyl-hexa-1,3-dien-1-yl phosphate. 
     
     
         8 . An isomer mixture M2 of a compound of formula 3 
       
         
           
           
               
               
           
         
         wherein R 2  is a linear alkyl group comprising 1 to 8 carbon atoms, R 3 , R 4  and R 5  are chosen independently from H and CH 3 , R 6  represents a linear or branched C 1 -C 6  alkyl group, having an isomeric purity greater than or equal to 98% in (E,Z) isomer and containing at least 0.1% of (Z,E) and (Z,Z) isomers and less than 1% of (E,E) isomer. 
       
     
     
         9 . The mixture M2 according to  claim 8 , wherein the compound of formula 3 is 7,9-dodecadienyl. 
     
     
         10 . The process according to  claim 1 , wherein the enol phosphate isomer mixture comprising a detectable quantity of (E,E) isomer of step a) is obtained from (E) hex-2-enal. 
     
     
         11 . The process according to  claim 1 , wherein the dienophile D is selected from the group consisting of maleic acid, acrylic acid, methacrylic acid, methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, n-butyl methacrylate, dimethyl maleate, diethyl maleate, and maleic anhydride. 
     
     
         12 . The process according to  claim 1 , wherein the acylation agent is chosen in the group comprising acetoyl halides, acetic anhydride and alkyl acetates.