1: 73 percent / 1.) n-butyllithium / tetrahydrofuran / Ambient temperature; 1.) 1h, 2.) 2h 2: 67 percent / conc.HCl / ethanol / 2 h / Heating 3: 79 percent / Tl(NO3)3*3H2O / methanol / -25 °C View Scheme