Sterically hindered pi-bridge nonlinear optical chromophores, processes including same, and devices therefrom

Abstract

In various embodiments, chromophores are described that include novel electron acceptors, novel electron donors, and/or novel conjugated bridges that are useful in nonlinear optical applications. In some embodiments, the present invention provides chromophore architectures wherein a chromophore contains more than one electron acceptor in electronic communication with a single electron donor, and/or more than one electron donor in electronic communication with a single electron acceptor. Also described is processes for providing materials comprising the novel chromophores and polymer matrices containing the novel chromophores. Electro-optic devices described herein contain one or more of the described electron acceptors, electron donors, conjugated bridges, or chromophores.

1 . A chromophore comprising a ring locked bithiophene π bridge having the formula  
     
       
         
         
             
             
         
       
       wherein, independently at each occurrence:  
       π 1  is absent or a bridge that provides electronic conjugation between D and the remainder of the molecule;  
       π 2  is absent or a bridge that provides electronic conjugation between A and the remainder of the molecule;  
       D is an electron donating group having low electron affinity relative to the electron affinity of A;  
       A is an electron accepting group having high electron affinity relative to the electron affinity of D;  
       X is O, S, Se or CR 2 ;  
       R is hydrogen, halogen, alkyl, aryl, or heteroalkyl;  
       n=1-4;  
       and any one of π 1 ,  π2 , D, or A can be further independently substituted with one or more halogen, alkyl, aryl, or heteroalkyl.  
     
   
   
       2 . The chromophore of  claim 1 , wherein D is selected from the group consisting of  
     
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       wherein, independently at each occurrence:  
       R 1  is alkyl, aryl or heteroalkyl;  
       R 2  is hydrogen, alkyl, aryl or heteroalkyl;  
       Y is O, S or Se;  
       m is 2, 3 or 4;  
       p is 0, 1 or 2; and  
       q is 0 or 1.  
     
   
   
       3 . The chromophore of  claim 2 , wherein D is selected from the group consisting of  
     
       
         
         
             
             
         
       
     
   
   
       4 . The chromophore of  claim 1 , wherein A is selected from the group consisting of  
     
       
         
         
             
             
         
       
       wherein, independently at each occurrence:  
       R 1  is alkyl, aryl or heteroalkyl;  
       R 2  is hydrogen, alkyl, aryl or heteroalkyl;  
       Y is O, S or Se; and  
       q is 0 or 1.  
     
   
   
       5 . The chromophore of  claim 4 , wherein A has the formula  
     
       
         
         
             
             
         
       
     
   
   
       6 . There chromophore of  claim 1  wherein π 1  and π 2  each independently comprise  
     
       
         
         
             
             
         
       
       wherein, independently at each occurrence:  
       Z 1  is O, S, Se, NR 1 , C(R 1 ) 2  or —C(R 1 )═C(R 1 )—;  
       p is 0, 1 or 2;  
       o is 0, 1 or 2;  
       o+p is at least 1;  
       R 2  is hydrogen, alkyl, aryl or heteroalkyl;  
       Z 2  has the formula  
       
         
           
           
               
               
           
         
       
       q is 0 or 1.  
     
   
   
       7 . The chromophore of  claim 6 , wherein π 1  and π 2  each independently comprise an alkene or a thiophene.  
   
   
       8 . The chromophore of  claim 7 , wherein the thiophene has the formula  
     
       
         
         
             
             
         
       
       wherein X is O or S and R 1  is alkyl, aryl or heteroalkyl.  
     
   
   
       9 . An electro-optic device comprising the chromophore of  claim 1 .  
   
   
       10 . An electro-optic device comprising the chromophore of  claim 2 .  
   
   
       11 . An electro-optic device comprising the chromophore of  claim 4 .  
   
   
       12 . An electro-optic device comprising the chromophore of  claim 6.