Polynitrogen systems

Notable in the series of homoleptic polynitrogen systems is the absence of the N ring. The structure of hexaazabenzene strongly depends on the choice of theoretical model and basis set [97] [112], van der Waals type structure of two... 

Other polynitrogen compounds containing the pentazole ring system 743... 

The many routes used to synthesize this system have been reviewed <86AHC(39)ll7>. Since the late 1980s, emphasis has been placed on the synthesis of TV-amino derivatives both for the production of the reactive species pyrimidyne and polynitrogen heterocycles. Hydrazine insertion into the triazoles (136) (Equation (16)) produces the 6-amino derivatives (105) <88LA1107> whilst diazotization of the aminohydrazino pyrimidine (137) (Equation (17)) forms the 3-amino derivative (138) (87JHC705). 

Veiga et al. (2013) developed a rapid method for efiScient palladium catalyzed N-arylation of polynitrogenated macrocycles. Its applicability for functionalization of protected azamacrocycles of various sizes with substituted aryl bromides of optional electronic properties has been established. The compatibility of the protocol with common N-protecting schemes as well as the impact of electronic versus steric factors was also discussed. This method provides moderate to excellent yields of N-arylated azamacrocycles (45-96%) using a commercially available catalytic system and easily available alkoxide or phenoxide base. 

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