hydrogenchloride in 1,4-dioxane T=90°C; 18 h;

hydrogenchloride in water 4.7 h; Heating;

1: p-TsOH*H2O / cyclohexane / 0.83 h / Heating; azeotropic dist. 2: 1.) S8 / 1.) MeOH, 15 min, RT, 2.) MeOH, 17 h 3: 80 percent / t-butylnitrite, CuCl2 / acetonitrile / 1.5 h, RT; 65 deg C, 2.5 h 4: 66 percent / 5percent aq. HCl / dioxane / 18 h / 90 °C View Scheme

1: 1.) S8 / 1.) MeOH, 15 min, RT, 2.) MeOH, 17 h 2: 80 percent / t-butylnitrite, CuCl2 / acetonitrile / 1.5 h, RT; 65 deg C, 2.5 h 3: 66 percent / 5percent aq. HCl / dioxane / 18 h / 90 °C View Scheme

1: 1.) S8 / 1.) MeOH, 15 min, RT, 2.) MeOH, 17 h 2: 80 percent / t-butylnitrite, CuCl2 / acetonitrile / 1.5 h, RT; 65 deg C, 2.5 h 3: 66 percent / 5percent aq. HCl / dioxane / 18 h / 90 °C View Scheme

1: 80 percent / t-butylnitrite, CuCl2 / acetonitrile / 1.5 h, RT; 65 deg C, 2.5 h 2: 66 percent / 5percent aq. HCl / dioxane / 18 h / 90 °C View Scheme