Other Catalytic Systems Causing Skeletal Rearrangement of Epimeric Aldoses

Other Catalytic Systems Causing Skeletal Rearrangement of Epimeric Aldoses 

In addition to molybdic acid, there have been reports of several other catalytic systems that cause mechanistically relative transformations of aldoses involving a 1,2-shift of their carbon skeleton. They include the nickel(II)-ethylenediamine [43] and cobalt(II)-ethylenediamine complexes [44] as well as the calciiun(II), strontium(II),lanthanum(III) and neodymium(III) cations in both aqueous and alcoholic alkaline solutions [45,46]. Unlike the BiTik reaction, all these transformations exploit rather equimolar amounts of the catalysts so that they result in thermodynamic equilibria of the catalytic complexes with the epimeric aldoses. Moreover, due to steric restrictions, the aforementioned alkaline earth and rare earth cations, which form mononuclear tetradentate complexes with aldoses. 

Application of the Bilik Reaction for the Mutual Interconversion of 2-Ketoses and 2-C-(Hydroxymethyl)aldoses 

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