1: 2-bromo-3-(n-hexyl)thiophene With magnesium in diethyl ether T=20°C; 2 h; 2: 2-isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane in diethyl ether T=20°C; 18 h; Further stages.;

1: {2-[4-(2-ethoxyethoxy)phenyl]ethyl}-[3-(n-hexyl)thiophen-2-yl]di-para-tolylgermane With boron trichloride; methyloxirane in n-heptane; dichloromethane T=-78°C; 0.666667 h; 2: 2,3-dimethylbutane-2,3-diol in n-heptane; dichloromethane T=20°C; Further stages.;

n-butyllithium in tetrahydrofuran n-BuLi added to soln. of thiophene in THF at -80°C, mixt. stirredat -80.degre.C for 1 h, B(i-PrO)3 added, mixt. allowed to warm to room temp., after 2 h at room temp. pinacol added, suspn. stirred overnight a t room temp.; THF taken off, residue dissolved in petrolether, filtered over neutral alumina, solvent taken off, dried under vac.;

1: 2-bromo-3-(n-hexyl)thiophene With n-butyllithium in tetrahydrofuran; hexane T=-80°C; 1 h; 2: With tri-isopropoxy-borane in tetrahydrofuran; hexane T=-78 - 20°C; 3: 2,3-dimethylbutane-2,3-diol in tetrahydrofuran; hexane T=20°C;

1: 3-Hexylthiophene With n-butyllithium; diisopropylamine in tetrahydrofuran; hexane T=-78°C; 2 h; 2: 2-isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane in tetrahydrofuran; hexane 1 h; Overall yield = 90 percent; Overall yield = 610 mg; regioselective reaction;

methyloxirane in dichloromethane (N2); treatment of germanium compd. with propilene oxide and boron compd. in CH2Cl2 at -78°C and then with pinacol room temp.;

1.1: N-bromosuccinmide; acetic acid / 0.5 h / 20 °C / |Inert atmosphere; |Darkness 2.1: n-butyllithium / tetrahydrofuran; hexane / 0.5 h / -78 °C / |Inert atmosphere 2.2: 12 h / 20 °C / |Inert atmosphere View Scheme

palladium

sodium hydrogencarbonate; tetrakis(triphenylphosphine) palladium(0) in ethylene glycol dimethyl ether 24 h; Heating;

tetrakis(triphenylphosphine) palladium(0); potassium carbonate in water; toluene T=90°C; Suzuki coupling; 6 h; Inert atmosphere; regioselective reaction;