1: SOCl2 / 4 h / 25 °C 2: 16 h / 25 °C View Scheme

1: POCl3 / 3 h / 110 - 120 °C 2: 1.) H2NOH*HCl/Na2CO3, 2.) Ac2O / 1.) MeOH, H2O, reflux, 3 h, 2.) reflux, 3 h 3: KOH / ethane-1,2-diol / 4 h / 167 °C 4: SOCl2 / 4 h / 25 °C 5: 16 h / 25 °C View Scheme

1: 1.) H2NOH*HCl/Na2CO3, 2.) Ac2O / 1.) MeOH, H2O, reflux, 3 h, 2.) reflux, 3 h 2: KOH / ethane-1,2-diol / 4 h / 167 °C 3: SOCl2 / 4 h / 25 °C 4: 16 h / 25 °C View Scheme

1: 74 percent / CH3COOH / 2 h / Heating 2: POCl3 / 3 h / 110 - 120 °C 3: 1.) H2NOH*HCl/Na2CO3, 2.) Ac2O / 1.) MeOH, H2O, reflux, 3 h, 2.) reflux, 3 h 4: KOH / ethane-1,2-diol / 4 h / 167 °C 5: SOCl2 / 4 h / 25 °C 6: 16 h / 25 °C View Scheme

T=25°C; 16 h; Yield given;

N-bromosuccinmide; 2,2'-azo-bisisobutyronitrile in tetrachloromethane 19 h; Heating;