ethanol; sodium ethanolate anschliessendes Ansaeuern mit wss. Salzsaeure;

benzenesulfonic Acid; benzene

bis(2-pyridinyl)-disulfide; triphenylphosphine in toluene 1.) 25 deg C, 3 h, 2.) reflux, 12 h;

1: 96 percent / K2CO3 / acetone / 1 h / Heating 2: 96 percent / HF, pyridine / tetrahydrofuran / 0.5 h / 0 °C 3: 95 percent / 1,3-dicyclohexylcarbodiimide (DCC), 4-(dimethylamino)pyridine (DMAP), camphorsulfonic acid (CSA) / CH2Cl2 / 4 h / 25 °C 4: 89 percent / HF, pyridine / tetrahydrofuran / 0 °C 5: 93 percent / H2 / 10percent Pd(OH)2/C / ethyl acetate / 2 h / Ambient temperature 6: 45 percent / triphenylphosphine, 2,2'-dipyridyl disulfide / toluene / 1.) 25 deg C, 3 h, 2.) reflux, 12 h View Scheme

1: 95 percent / 1,3-dicyclohexylcarbodiimide (DCC), 4-(dimethylamino)pyridine (DMAP), camphorsulfonic acid (CSA) / CH2Cl2 / 4 h / 25 °C 2: 89 percent / HF, pyridine / tetrahydrofuran / 0 °C 3: 93 percent / H2 / 10percent Pd(OH)2/C / ethyl acetate / 2 h / Ambient temperature 4: 45 percent / triphenylphosphine, 2,2'-dipyridyl disulfide / toluene / 1.) 25 deg C, 3 h, 2.) reflux, 12 h View Scheme

1: 96 percent / HF, pyridine / tetrahydrofuran / 0.5 h / 0 °C 2: 95 percent / 1,3-dicyclohexylcarbodiimide (DCC), 4-(dimethylamino)pyridine (DMAP), camphorsulfonic acid (CSA) / CH2Cl2 / 4 h / 25 °C 3: 89 percent / HF, pyridine / tetrahydrofuran / 0 °C 4: 93 percent / H2 / 10percent Pd(OH)2/C / ethyl acetate / 2 h / Ambient temperature 5: 45 percent / triphenylphosphine, 2,2'-dipyridyl disulfide / toluene / 1.) 25 deg C, 3 h, 2.) reflux, 12 h View Scheme

1: 93 percent / H2 / 10percent Pd(OH)2/C / ethyl acetate / 2 h / Ambient temperature 2: 45 percent / triphenylphosphine, 2,2'-dipyridyl disulfide / toluene / 1.) 25 deg C, 3 h, 2.) reflux, 12 h View Scheme

p-NO2-benzoic anhydride; scandium tris(trifluoromethanesulfonate) in tetrahydrofuran; acetonitrile 5 h; Heating; Yields of byproduct given;

1: HBr / acetic acid / 100 °C 2: 88 percent Chromat. / Cs2CO3 / dimethylformamide / 40 °C View Scheme

1,8-diazabicyclo[5.4.0]undec-7-ene in tetrahydrofuran 100 h; polymer-supported synthesis on polystirene; Further byproducts given;