A Mild Chemo-Enzymatic Oxidation–Hydrocyanation Protocol

Oxidation-hydrocyanation of γ,δ-unsaturated alcohols using (immobilised) TEMPOXPhI(OAc)2 in combination with HbHNL proceeds smoothly. After (in situ) protection, the resulting cyanohydrin derivatives were obtained in good overall yields and high ee's. A mild TEMPO-catalysed oxidation protocol is described that yields β,γ-unsaturated aldehydes without isomerisation of the double bond and that is compatible with a subsequent HbHNL-catalysed hydrocyanation performed in the same solvent system. © Wiley-VCH Verlag GmbH & Co. KGaA, 2006.