1: With n-butyllithium in tetrahydrofuran; hexane 1.16667 h; 2: With boric acid trimethyl ester in tetrahydrofuran; hexane 0.5 h; 3: With hydrogenchloride in tetrahydrofuran; hexane

in benzene 48 h; Heating;

magnesium sulfate in acetone Heating;