FeBr2 in 1,2-dichloro-ethane T=110°C; 20 h; Inert atmosphereSealed tube; optical yield given as percent destereoselective reaction;

iron(III) chloride in dichloromethane T=20°C;

oxalyl dichloride; N,N-dimethyl-formamide in dichloromethane T=25°C; 15 h; Yield given. Yields of byproduct given. Title compound not separated from byproducts;