MnI2; n-butyllithium in diethyl ether T=-20°C;

aluminium trichloride in carbon disulfide T=0°C; 0.5 h;

sulfuric acid in water; acetone 5 h; Heating;

1: 1.) THF, EtMgBr, RT, 1 h; 2.) diethyl ether, -25 deg C for 45 min then 1 h at RT then 15 min at 30 deg C 2: 81 percent / p-toluenesulfonic acid / benzene / Heating 3: 1.) BuLi / 1.) THF, -65 deg C, 30 min; 2.) THF, overnight, -65 deg C to 25 deg C 4: 86 percent / H2SO4 / acetone; H2O / 5 h / Heating View Scheme

1: 81 percent / p-toluenesulfonic acid / benzene / Heating 2: 1.) BuLi / 1.) THF, -65 deg C, 30 min; 2.) THF, overnight, -65 deg C to 25 deg C 3: 86 percent / H2SO4 / acetone; H2O / 5 h / Heating View Scheme

1: 1.) BuLi / 1.) THF, -65 deg C, 30 min; 2.) THF, overnight, -65 deg C to 25 deg C 2: 86 percent / H2SO4 / acetone; H2O / 5 h / Heating View Scheme

diboron trioxide; oxygen 1.) 45 deg C, 60 h, 2.) 110 deg C, 2 h; Yield given. Yields of byproduct given. Title compound not separated from byproducts;

1: n-butyllithium 2: dipyridinium dichromate View Scheme

dipyridinium dichromate