Structure and stability, as a function of pH, of borate esters of carbohydrate oximes and related compounds in aqueous media studied by 11B and 13C NMR spectroscopy
Abstract
Borate ester formation of carbohydrate oximes and related compounds, including acetohydroxamic acid, has been studied using 11B and 13C NMR spectroscopy. It is shown that the oxime hydroxyl is involved in the borate ester formation. The resulting six-membered ring borate monoesters are more stable than the five-membered ring erythro- or threo-borate monoesters involving a vicinal diol function.