1: SOCl2 / CHCl3 / 1 h / Heating 2: dimethylformamide / 1 h / Ambient temperature 3: 65 percent / piperidine / ethanol / 18 h / Heating 4: 56 percent / NaBH4, 1.0N aq. NaOH, CoCl2*6H2O, 2,2'-dipyridyl / dimethylformamide; tetrahydrofuran / 18 h / Ambient temperature 5: 72 percent / 4N aq. HCl / 18 h / Heating View Scheme

1: dimethylformamide / 1 h / Ambient temperature 2: 65 percent / piperidine / ethanol / 18 h / Heating 3: 56 percent / NaBH4, 1.0N aq. NaOH, CoCl2*6H2O, 2,2'-dipyridyl / dimethylformamide; tetrahydrofuran / 18 h / Ambient temperature 4: 72 percent / 4N aq. HCl / 18 h / Heating View Scheme

1: 65 percent / piperidine / ethanol / 18 h / Heating 2: 56 percent / NaBH4, 1.0N aq. NaOH, CoCl2*6H2O, 2,2'-dipyridyl / dimethylformamide; tetrahydrofuran / 18 h / Ambient temperature 3: 72 percent / 4N aq. HCl / 18 h / Heating View Scheme

1: 96 percent / 2N aq. HCl / methanol / 2 h / Heating 2: SOCl2 / CHCl3 / 1 h / Heating 3: dimethylformamide / 1 h / Ambient temperature 4: 65 percent / piperidine / ethanol / 18 h / Heating 5: 56 percent / NaBH4, 1.0N aq. NaOH, CoCl2*6H2O, 2,2'-dipyridyl / dimethylformamide; tetrahydrofuran / 18 h / Ambient temperature 6: 72 percent / 4N aq. HCl / 18 h / Heating View Scheme

1: 1.) aq. HBr, NaNO2, 2.) Cu2O / 1.) acetone, 5 deg C, 2.) acetone 2: 38 percent / NaOAc / ethanol / 5 h / Heating 3: 79 percent / 4N HCl / 24 h / Heating View Scheme

1: 38 percent / NaOAc / ethanol / 5 h / Heating 2: 79 percent / 4N HCl / 24 h / Heating View Scheme