1: phenylacetylene With n-butyllithium in tetrahydrofuran; hexane T=-78 - 20°C; 0.333333 h; Inert atmosphere; 2: 5,12-naphthacenequinone in tetrahydrofuran; hexane T=-78 - 20°C; 1.25 h; Inert atmosphere; 3: With hydrogenchloride; SnCl2·2H2O in tetrahydrofuran; hexane; water T=20°C; Inert atmosphere;

tin(ll) chloride in 1,4-dioxane; acetic acid

tin(ll) chloride in 1,4-dioxane; acetic acid

(i) aq. NH4Cl, (ii) SnCl2*2H2O; Multistep reaction;