manganese(IV) oxide in 1,2-dichloro-ethane 5 h; Heating;

sulfuric acid Ambient temperatureovernight;

1: 82 percent / xylene / 0.5 h / Heating 2: 78 percent / conc. H2SO4 / Ambient temperature; overnight View Scheme

1: 1. potassium t-butoxide, diethyl chlorophosphate; 2. potassium t-butoxide / 1. THF, 10min.; 2. DMF, 1h 2: 98 percent / trifluoroacetic acid / 2 h / Ambient temperature 3: 82 percent / xylene / 0.5 h / Heating 4: 78 percent / conc. H2SO4 / Ambient temperature; overnight View Scheme