1: With sodium tetrahydroborate; iodine in tetrahydrofuran T=0°C; 4 h; Inert atmosphereReflux; 2: With hydrogenchloride in tetrahydrofuran; water 0.5 h; Reflux;

1.1: potassium carbonate / N,N-dimethyl-formamide / 12 h / 140 °C 2.1: sodium tetrahydroborate; iodine / tetrahydrofuran / 4 h / 0 °C / |Inert atmosphere; |Reflux 2.2: 0.5 h / |Reflux View Scheme

1.1: potassium carbonate / N,N-dimethyl-formamide / 12 h / 140 °C 2.1: sodium tetrahydroborate; iodine / tetrahydrofuran / 4 h / 0 °C / |Inert atmosphere; |Reflux 2.2: 0.5 h / |Reflux View Scheme