dipyridinium dichromate in N,N-dimethyl-formamide 12 h;

1: 1.) n-BuLi, hexamethylphosphoramide (HMPA) / 1.) hexane, 5 deg C, 30 min, 2.) RT, overnight 2: p-toluenesulfonic acid / methanol / 1.5 h 3: 48 percent / Li, 1,3-diaminopropane, potassium tert-butoxide / 2 h 4: 86 percent / pyridinium dichromate (PDC) / dimethylformamide / 9 h View Scheme

1: 87 percent / p-toluenesulfonic acid / CH2Cl2 / 1.67 h / 0 - 20 °C 2: 1.) n-BuLi, hexamethylphosphoramide (HMPA) / 1.) hexane, 5 deg C, 30 min, 2.) RT, overnight 3: p-toluenesulfonic acid / methanol / 1.5 h 4: 48 percent / Li, 1,3-diaminopropane, potassium tert-butoxide / 2 h 5: 86 percent / pyridinium dichromate (PDC) / dimethylformamide / 9 h View Scheme

1: 48 percent / Li, 1,3-diaminopropane, potassium tert-butoxide / 2 h 2: 86 percent / pyridinium dichromate (PDC) / dimethylformamide / 9 h View Scheme

1: 53 percent / KH, 1,3-diaminopropane / 3.5 h / 0 - 20 °C 2: 60 percent / CrO3, H2SO4 / acetone / 16 h / 10 °C View Scheme

1: 29.6 g / diethyl ether / 2 h / Ambient temperature 2: 100 percent / Br2 / CHCl3 3: 95 percent / 1,8-diazabicyclo<5.4.0>undec-7-ene (DBU) / 12 h / 140 °C 4: 71 percent / LAH / diethyl ether / 4 h 5: 53 percent / KH, 1,3-diaminopropane / 3.5 h / 0 - 20 °C 6: 60 percent / CrO3, H2SO4 / acetone / 16 h / 10 °C View Scheme

1: 100 percent / Br2 / CHCl3 2: 95 percent / 1,8-diazabicyclo<5.4.0>undec-7-ene (DBU) / 12 h / 140 °C 3: 71 percent / LAH / diethyl ether / 4 h 4: 53 percent / KH, 1,3-diaminopropane / 3.5 h / 0 - 20 °C 5: 60 percent / CrO3, H2SO4 / acetone / 16 h / 10 °C View Scheme

1: 97 percent / chlorotrimethylsilane, sodium iodide / acetonitrile / 1.5 h / 70 °C 2: 1.) hexamethylphosphoramide (HMPA) / 1.) RT, 45 min, 2.) 0 deg C, 30 min View Scheme

1: 71 percent / LAH / diethyl ether / 4 h 2: 53 percent / KH, 1,3-diaminopropane / 3.5 h / 0 - 20 °C 3: 60 percent / CrO3, H2SO4 / acetone / 16 h / 10 °C View Scheme

1: 95 percent / 1,8-diazabicyclo<5.4.0>undec-7-ene (DBU) / 12 h / 140 °C 2: 71 percent / LAH / diethyl ether / 4 h 3: 53 percent / KH, 1,3-diaminopropane / 3.5 h / 0 - 20 °C 4: 60 percent / CrO3, H2SO4 / acetone / 16 h / 10 °C View Scheme