1: 2-methyl-thiophene With n-butyllithium in diethyl ether; hexane T=0°C; 1.5 h; Inert atmosphereSchlenk technique; 2: indole-2,3-dione in diethyl ether; hexane T=20°C; 6 h; Inert atmosphereSchlenk technique; 3: With lithium aluminium tetrahydride in diethyl ether; hexane 3 h; RefluxInert atmosphereSchlenk technique;