1: With n-butyllithium in tetrahydrofuran; hexane T=-78°C; 1 h; 2: With boric acid trimethyl ester in tetrahydrofuran; hexane T=-78 - 20°C; 3.5 h; 3: With hydrogenchloride in tetrahydrofuran; hexane; water

in toluene

in benzene 3 h; Heating;