1: 69 percent / Fremy's salt, KH2PO4 / H2O; ethanol / 0.67 h / 0 °C 2: 1) BF3*Et2O, 2) chloranil / 1) CH2Cl2, -40 deg C, 3 h, 2) m-xylene, 140 deg C, 24 h View Scheme

1: 84 percent / 36percent HCl / methanol / 1.17 h / Heating 2: 69 percent / Fremy's salt, KH2PO4 / H2O; ethanol / 0.67 h / 0 °C 3: 1) BF3*Et2O, 2) chloranil / 1) CH2Cl2, -40 deg C, 3 h, 2) m-xylene, 140 deg C, 24 h View Scheme

1: 92 percent / K2CO3 / methanol / 0 °C 2: 69 percent / Fremy's salt, KH2PO4 buffer / H2O / 0 °C 3: 2.) chloranil, oxygen / 1.) CH2Cl2, RT, 4 d, 2.) xylene, 140 deg C View Scheme

TiCl2(OPri)2; chloranil 1) CH2Cl2, -50 deg C, 17 h, 2) m-xylene, 140 deg C, 24 h; Yield given. Multistep reaction. Title compound not separated from byproducts;

oxygen; chloranil 1.) CH2Cl2, RT, 4 d, 2.) xylene, 140 deg C; Yield given. Multistep reaction. Yields of byproduct given;