Process for preparing pentacene derivatives

Abstract

A process for preparing substituted pentacene compounds comprises the step of cyclizing substituted bis(benzyl)phthalic acids using an acid composition comprising trifluoromethanesulfonic acid, the substituted bis(benzyl)phthalic acids being represented by the following general formulas: wherein each R (that is, each of the groups R 1 through R 8 ) is independently an electron-donating group, a halogen atom, a hydrogen atom, or a combination thereof.

1 . A process for preparing pentacene compounds comprising the steps of: 
 (i) preparing a substituted bis(benzyl)phthalic acid by (a) reacting (1) at least one substituted benzene selected from those represented by the following general formulas:                          wherein each R group is independently selected from the group consisting of electron-donating groups, halogen atoms, hydrogen atoms, and combinations thereof; with (2) pyromellitic dianhydride (or a derivative of pyromellitic dianhydride) to form a substituted bis(benzoyl)phthalic acid; and (b) reducing said substituted bis(benzoyl)phthalic acid to the corresponding substituted bis(benzyl)phthalic acid; and    (ii) cyclizing said substituted bis(benzyl)phthalic acid to form the corresponding substituted pentacenedione by using an acid composition comprising trifluoromethanesulfonic acid, said substituted bis(benzyl)phthalic acid being selected from those represented by the following general formulas:                          
     
     
         2 . A process for preparing pentacene compounds comprising the steps of (a) reacting (1) at least one substituted benzene selected from those represented by the following general formulas:  
       
         
           
           
               
               
           
         
       
       wherein each of the groups R 1  through R 8  is independently selected from the group consisting of alkyl groups and hydrogen atoms; with (2) pyromellitic dianhydride (or a derivative of pyromellitic dianhydride) to form a substituted bis(benzoyl)phthalic acid; (b) reducing said substituted bis(benzoyl)phthalic acid to the corresponding substituted bis(benzyl)phthalic acid; (c) cyclizing said substituted bis(benzyl)phthalic acid to form the corresponding substituted pentacenedione by using an acid composition comprising trifluoromethanesulfonic acid; (d) reducing said substituted pentacenedione to the corresponding substituted pentacenediol; and (e) dehydrating said substituted pentacenediol to the corresponding substituted pentacene.  
     
     
         3 . A process for preparing a diaryl cyclic ketone comprising the step of cyclizing a diaryl carboxylic acid comprising at least two aromatic rings, one said ring having at least one aromatic ring carbon atom that is directly bonded to a carboxylic acid moiety, and another said ring having at least one aromatic ring carbon atom that is capable of undergoing aromatic electrophilic substitution with said carboxylic acid moiety; said cyclizing being effected by using an acid composition comprising trifluoromethanesulfonic acid.  
     
     
         4 . The process of  claim 3  wherein said diaryl carboxylic acid is 2,5-dibenzylterephthalic acid or 4,6-dibenzylisophthalic acid.  
     
     
         5 . The process of  claim 3  wherein said diaryl carboxylic acid is substituted.  
     
     
         6 . A process for preparing acenes comprising the step of treating at least one diarene-annellated cyclohexanone, cyclohexa-1,2-dione, or cyclohexa-1,4-dione with aluminum alkoxide.  
     
     
         7 . Substituted pentacenedione compounds represented by the following general formulas:  
       
         
           
           
               
               
           
         
       
       wherein each R group is independently selected from the group consisting of electron-donating groups, halogen atoms, hydrogen atoms, and combinations thereof.  
     
     
         8 . The compounds of  claim 7  wherein each said R group is independently selected from the group consisting of alkyl groups and hydrogen atoms.