Iron-catalysed chemo-selective oxidation of unprotected sugars: application for the competitive oxidation of pentoses from a sugar mixture

Abstract

An iron-catalysed transfer hydrogenation methodology was developed to oxidise aldo-hexoses and -pentoses into sugar lactones using different acceptors. The transformation occurs on unprotected sugars with complete chemo-selectivity for the anomeric position. An application for the competitive oxidation of pentose from a mixture of C5 and C6 sugars is also reported. Finally, we managed to perform the oxidation of xylose with only an equimolar amount of a carefully chosen acceptor, improving drastically the sustainability of the transformation without compromising the equilibrium shift.