1: camphorsulfonic acid / 9 h / Heating 2: 97 percent / H2 / Pd/C / ethanol / Ambient temperature View Scheme

1: camphorsulfonic acid / 9 h / Heating 2: 97 percent / H2 / Pd/C / ethanol / Ambient temperature 3: 84 percent / pyridine / 1 h / Ambient temperature 4: 82 percent / PPTS / benzene / 2 h / Heating View Scheme

dihydrogen peroxide in acetonitrile T=25°C; 4 h;

ammonium chloride; zinc in diethyl ether; water Reduction; 8 h;

1.1: water; zinc; ammonium chloride / diethyl ether / 4 h / 20 °C 2.1: Aliquatreg; 336; sodium hydroxide / diethyl ether; water / 21 h / 20 °C 3.1: trichlorophosphate / |Cooling with ice 3.2: 3 h / 20 °C 3.3: |Cooling with ice View Scheme

1.1: water; zinc; ammonium chloride / diethyl ether / 4 h / 20 °C 2.1: Aliquatreg; 336; sodium hydroxide / diethyl ether; water / 21 h / 20 °C 3.1: trichlorophosphate / |Cooling with ice 3.2: 3 h / 20 °C 3.3: |Cooling with ice 4.1: ammonium acetate / 2 h / |Reflux View Scheme

camphor-10-sulfonic acid 9 h; Heating; Yield given;

1: water; zinc; ammonium chloride / diethyl ether / 4 h / 20 °C 2: Aliquatreg; 336; sodium hydroxide / diethyl ether; water / 21 h / 20 °C View Scheme