1: With titanium(IV) isopropylate; ammonia in ethanol T=25°C; 6 h; 2: With sodium tetrahydroborate in ethanol T=25°C; 3 h; Further stages.;

1: benzene / Heating 2: 71 percent / dioxane / 1.) 100 min, 2.) reflux, 22 h 3: hydrogen / 10 percent palladium/charcoal / ethanol; H2O / Ambient temperature 4: 32 percent / conc. hydrochloric acid / ethanol; H2O / 2.5 h / Heating 5: 60 percent / 6 N hydrochloric acid / 7.5 h / Heating 6: 27 percent / 10 percent palladium/charcoal / various solvent(s) / 50 h / Heating 7: 71 percent / hydrogen chloride / methanol; pyridine / 0.67 h / 190 °C View Scheme

sodium tetrahydroborate in methanol T=20°C; 3 h;

triethylsilane; NaPF6; dirhenium heptaoxide in dichloromethane T=50°C; 12 h; chemoselective reaction;

sodium cyanoborohydride in hydrogenchloride; ethanol T=20°C; pH=6; 96 h;

1: benzene / Heating 2: 71 percent / dioxane / 1.) 100 min, 2.) reflux, 22 h 3: hydrogen / 10 percent palladium/charcoal / ethanol; H2O / Ambient temperature 4: 32 percent / conc. hydrochloric acid / ethanol; H2O / 2.5 h / Heating 5: 60 percent / 6 N hydrochloric acid / 7.5 h / Heating 6: 27 percent / 10 percent palladium/charcoal / various solvent(s) / 50 h / Heating View Scheme