sodium hydride in benzene 1.) 80 deg C, 5 h, 2.) r.t., overnight;

triflic acid-d1 in chloroform-d1 T=20°C; Inert atmosphere;

1: 79.1 percent / NaH / benzene / 3 h / Heating 2: 84.8 percent / NaH / benzene / 1.) 80 deg C, 5 h, 2.) r.t., overnight View Scheme

potassium hydroxide in methanol 48 h; Ambient temperature;

1: 98 percent / 10percent KOH / methanol / 48 h / Ambient temperature 2: 64.1 percent / 0.17 h / 165 - 170 °C 3: 31.3 percent / BuLi, diisopropylamine, HMPA / tetrahydrofuran / 1.) -78 deg C, 30 min, 2.) -40 deg C, 90 min 4: 30percent H2O2, HOAc / tetrahydrofuran / 1 h / 0 °C View Scheme