H Dependent Redox Behavior

The redox behavior of PABA in the presence of D-fructose and fluoride up to neutral pH values is typical of the emeraldine salt form of polyaniline [41], Under weakly acidic and neutral pH conditions, the 

BORONIC ACID SUBSTITUTED SELF-DOPED POLYANIUNE 

The role of D-fructose, fluoride, and pH in the structure formed with boronic acid has been investigated with NMR spectroscopy of monomer solutions at different pH values in the presence of D-fructose, with and without fluoride. For example, B and F NMR can be used to determine the structure of the boron (neutral trigonal vs anionic tetrahedral) and the involvement of fluoride in the complex (free vs complexed fluoride). The B chemical shift of a tetrahedral boronate appears approximately 20 ppm upfield from the trigonal boronic acid 

Shifts measured relative to reference borontrifluoride etherate and hexafluorobenzene 

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