(R)-oxynitrilase in di-isopropyl ether 20 h; Ambient temperature; Yield given;

in water

1: 2,2-Dimethyl-[1,3]dioxane-4,6-dione; phenol in toluene 5 h; Reflux; 2: 3,4-dihydroxy-benzaldehyde With piperidine; pyridine in toluene T=20°C; 12 h;

1.1: sodium hydride / mineral oil; N,N-dimethyl-formamide / 0.5 h / 0 °C / |Inert atmosphere 1.2: 18 h / 20 °C / |Inert atmosphere 2.1: dichloromethane / 15 h / 0 - 20 °C / |Inert atmosphere 3.1: triphenylphosphine; di-isopropyl azodicarboxylate / toluene / 3 h / 60 °C / |Inert atmosphere 4.1: dimethylsulfide; aluminum tri-bromide / dichloromethane / 5.5 h / 5 - 10 °C / |Inert atmosphere 5.1: (benzotriazo-1-yloxy)tris(dimethylamino)phosphonium hexafluorophosphate; N-ethyl-N,N-diisopropylamine / N,N-dimethyl-formamide / 18 h / 20 °C / |Inert atmosphere 6.1: tris(dimethylamino)-sulphonium difluorotrimethylsilicate / N,N-dimethyl-formamide / 4.5 h / 0 °C / |Inert atmosphere View Scheme

1: 64 percent / NaOAc / 5 h / 120 °C 2: 86 percent / 0.2 N HCl / 1 h / 100 °C View Scheme