lithium azide in ethanol 2 h; Heating;

1: 1.) hexamethylphosphoramide (HMPA), n-butyllithium / 1.) THF, hexane, -78 deg C, 1 h, 2.) 90 min 2: 69 percent / dichloroacetic acid / CH2Cl2 / 0.17 h 3: 67 percent / triethylamine, 4-dimethylaminopyridine (DMAP) / dimethylformamide / Ambient temperature 4: 90 percent / red mercuric oxide, mercuric chloride / tetrahydrofuran; H2O / 0.08 h / 0 °C 5: 78 percent / sodium borohydride / ethanol; H2O / 0.5 h / Ambient temperature 6: 94 percent / tetrabutylammonium fluoride / tetrahydrofuran View Scheme

1: 20 percent / LiN3 / ethanol / 2 h / Heating 2: 47 percent / DAST / benzene / 2 h / Ambient temperature View Scheme

1: 1.) hexamethylphosphoramide (HMPA), n-butyllithium / 1.) THF, hexane, -78 deg C, 1 h, 2.) 90 min 2: 69 percent / dichloroacetic acid / CH2Cl2 / 0.17 h 3: 67 percent / triethylamine, 4-dimethylaminopyridine (DMAP) / dimethylformamide / Ambient temperature 4: 90 percent / red mercuric oxide, mercuric chloride / tetrahydrofuran; H2O / 0.08 h / 0 °C 5: 59 percent / tetrabutylammonium fluoride / tetrahydrofuran / 0.12 h View Scheme

1: 1.) hexamethylphosphoramide (HMPA), n-butyllithium / 1.) THF, hexane, -78 deg C, 1 h, 2.) 90 min 2: 69 percent / dichloroacetic acid / CH2Cl2 / 0.17 h View Scheme

1: 20 percent / LiN3 / ethanol / 2 h / Heating 2: 47 percent / DAST / benzene / 2 h / Ambient temperature 3: 60 percent / 80percent aq. AcOH / 0.25 h / Heating View Scheme

KHF2; 4,4'-diaminostilbene-2,2'-disulfonic acid 1.) EtOCH2CH2OH, water, 145 deg C, 15 h, 2.) benzene, RT, 2 h; Yield given. Multistep reaction;

1: 30 percent / LiN3 / ethanol / 2 h / Heating 2: 65 percent / DAST / benzene / 2 h / Ambient temperature 3: 64 percent / 80percent aq. AcOH / 0.25 h / Heating View Scheme

1: 30 percent / LiN3 / ethanol / 2 h / Heating 2: 65 percent / DAST / benzene / 2 h / Ambient temperature View Scheme

1: 1.) NaH / 1.) DMF, room temp., 15 min, 2.) 100 deg C, 16 h 2: 98 percent / 4-(dimethylamino)pyridine / acetonitrile / 1 h / Ambient temperature 3: 38 percent / n-tributyltin hydride, 2,2'-azobis(2-methylpropionitrile) (AIBN) / toluene / 2.5 h / 100 °C 4: 75 percent / AcOH / methanol / 1 h / 100 °C View Scheme