1: 2-chloro-ethanol With tetra-(n-butyl)ammonium iodide; potassium iodide in tetrahydrofuran; N,N-dimethyl-formamide T=80°C; 24 h; polystyrene/1percent divinylbenzene resin; Inert atmosphere; 2: With acetic anhydride; 1,8-diazabicyclo[5.4.0]undec-7-ene in tetrahydrofuran T=0 - 20°C; polystyrene/1percent divinylbenzene resin; 3: p-chlorophenylazide Further stages;

1: in dimethyl sulfoxide T=20°C; 0.25 h; 2: With water in dimethyl sulfoxide

copper(l) iodide; triethylamine in dimethyl sulfoxide T=20°C; P=760.051 Torr; 24 h;

copper(l) iodide; Na-ascorbate in water; acetonitrile T=20°C; 6 h;

copper(l) iodide; 1,8-diazabicyclo[5.4.0]undec-7-ene; sodium L-ascorbate in N,N-dimethyl-formamide T=25°C; 18 h; Sealed tubeInert atmosphere;

potassium hydroxide in methanol 0.5 h; Heating;

potassium hydroxide in methanol Heating;

1: 62 percent / neat (no solvent) / 624 h / Ambient temperature 2: 84 percent / 2N KOH / methanol / 0.5 h / Heating View Scheme

in ethanol 38.5 h; Heating;

in ethanol Heating;