Figure 1: Oxidative ring expansion of furylcarbinols: historical precedent and modern interpretation.
From: Enzymatic aerobic ring rearrangement of optically active furylcarbinols
(a) Formation of 2,5-dimethoxy-2,5-dihydrofuran on oxidation with bromine in methanol is followed by acetal cleavage and ring expansion via an intermediate 4-ketoenal. (b) Schematic representation of the coupled biocatalytic Achmatowicz rearrangement combining aerobic reduction of oxygen by glucose to hydrogen peroxide with the peroxidase-mediated oxygen transfer onto the furan core.
