Other Nitrogen Transformation Rates

Pyridine has found some use as a catalyst for the transformation— especially in applications to ketose synthesis. The base has usually been employed as both catalyst and solvent (in anhydrous form). Under these conditions, it appears to act sluggishly—a conclusion which, since anhydrous pyridine solutions of a reducing sugar contain no acid except the sugar itself, is in accord with the idea that the transformation requires an acid as well as a base for its catalysis. The possibility of increasing the reaction rates by incorporating an appropriate acid catalyst, such as phenol, into these pyridine mixtures should be explored. Other nitrogenous bases which have been reported as catalysts for the transformation are ammonia, quinoline, and quinaldinc. ... 

Compound LII, on the other hand, can be made readily. It can have either the planar tricovalent boron structure or the "triptych tetra-covalent structure. In the latter structure the nitrogen is attached to boron and should be considerably less basic and nucleophilic than usual. It does in fact react unusually slowly with methyl iodide and with acids. The neutralization reaction with acids in water is not only slow but of zero order with respect to the acid. It is believed to have a rate-determining transformation from the triptych to the more basic form as the first step. 

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