1: With borane-THF in tetrahydrofuran T=65°C; 24 h; 2: With hydrogenchloride in tetrahydrofuran T=20°C; 1 h; 3: With diethylamine in tetrahydrofuran T=20°C; 16 h; Further stages.;

1.1: BH3*THF / tetrahydrofuran / 24 h / 65 °C 1.2: aq. HCl / tetrahydrofuran / 1 h / 20 °C 1.3: 84 percent / Et2NH / tetrahydrofuran / 16 h / 20 °C 2.1: 82 percent / 24 h / 120 °C 3.1: 86 percent / polymer-supported chromic acid / tetrahydrofuran / 48 h / Heating 4.1: 99 percent / piperazinomethyl polystyrene / toluene / 24 h / 88 °C View Scheme

1.1: borane-THF / 65 °C 1.3: SCX-2 2.1: 120 °C 3.1: PS-CrO3 / tetrahydrofuran 4.1: piperidine / toluene / 2 h / 80 °C 5.1: iodine; magnesium / methanol / 3 h / Reflux View Scheme

1.1: BH3*THF / tetrahydrofuran / 24 h / 65 °C 1.2: aq. HCl / tetrahydrofuran / 1 h / 20 °C 1.3: 84 percent / Et2NH / tetrahydrofuran / 16 h / 20 °C 2.1: 82 percent / 24 h / 120 °C 3.1: 86 percent / polymer-supported chromic acid / tetrahydrofuran / 48 h / Heating View Scheme