1: phenyl trifluoromethyl ether With N,N,N',N,-tetramethylethylenediamine; sec.-butyllithium in tetrahydrofuran; cyclohexane T=-75°C; 2 h; 2: methyl iodide in tetrahydrofuran; cyclohexane T=-75°C; Further stages.;

T=650°C; through quartz tube packed with platinum wire;

sodium in tetrahydrofuran T=80°C; 24 h; chemoselective reaction;