Boronates in Chemical Reactions

Boronates in Chemical Reactions 1. Boronates in Aqueous Systems 

With colleagues,5 he then proceeded to examine this complexing for a range of substituted phenylboronic acids (as part of a study of their influence in certain aspects of plant biochemistry), and found that, as expected, electron-withdrawing groups on the aromatic ring increased the stability of the complexes formed. 

Yurkevich and coworkers,65 using the pH-depression procedure, reported complexing constants of nucleosides and nucleotides, and showed that the depressions are themselves pH-dependent, adenosine exhibiting maximal effects near pH 7.8, 7.3, and 8.2 on mixing with 

Other compounds examined by this type of procedure are the 2, 3 -phenylboronates of nucleosides,27 28,36 and the butyl- and phenylboronates of D-xylose and L-arabinose,4 and these, also, are hydrolytically unstable. 

It is here concluded that carbohydrate boronic esters should normally be treated as being readily susceptible to hydrolysis and, presumably, alcoholysis, and that their occasional isolation in crystalline form from aqueous solvents8,23,70 or ethanol67 should be 

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