Ex parte BASHIR-HASHEMI - Page 2

          Appeal No. 1996-0709                                                        
          Application No. 08/228,245                                                  

               Considerable effort in recent years has been                           
               directed toward the synthesis of polynitrocubanes                      
               because of the potential use of this class of                          
               energetic materials as explosives, propellants,                        
               fuels and binders (Chemistry of Energetic Materials;                   
               Ed., G.A. Olah; D.R. Squire; Academic Press, Inc.,                     
               San Diego, CA, 1991.  Also see Carbocyclic Cage                        
               Compounds; Ed., E.J. Osawa; O. Yonemitsu; VCH                          
               Publishers, Inc., New York, NY, 1992).  The compact                    
               structures of cage molecules result in high                            
               densities, and the introduction of NO  groups further                  
               enhances the density.  The strain energy present in                    
               the cubane skeleton (>166 kcal/mol) is an added                        
               bonus to its performance.  Furthermore, preliminary                    
               results with polynitrocubanes indicate that such                       
               compounds are thermally very stable and are also                       
               very insensitive energetic materals.  Consequently,                    
               it is of interest to introduce functional groups on                    
               the cubane skeleton which can be converted to nitro                    
               group or other active functionalities.                                 
               Direct functionalization of nitrocubanes, while                        
               an attractive approach, has not heretofore been                        
               realized.  Cationic or anionic reactions, due to the                   
               activity of the nitro groups give either decomposed                    
               products or recovered starting materials.  We report                   
               here an efficient direct functionalization of a                        
               nitrocubane molecule by its irradiation in a                           
               solution of oxalyl halide (for a related case see                      
               Wiberg, K.B.; 10  Annual Working Group Meeting, Juneth                                                     
               3-6, 1992, Kiamesha Lake, NY.  For much simpler                        
               cases see Wiberg, K.B.; Williams, Jr., V.Z.; J. Org.                   
               Chem., 1970, 35 369; Applequist, D.E.; Saski, T.; J.                   
               Org. Chem.; 1978, 43, 2399).  This new and                             
               potentially powerful synthetic development will                        
               greatly shorten the number of steps necessary to                       
               obtain nitrocubane derivatives which are otherwise                     
               difficult to synthesize.                                               


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