1: 55 percent / anhydrous potassium carbonate / 30 h / Ambient temperature 2: 43 percent / pyrolysis in an apparatus described in J.Am.Chem.(19)Soc83, 105, 7696 View Scheme

triethylamine; bis-triphenylphosphine-palladium(II) chloride in acetonitrile; benzene T=100°C; P=31028.9 Torr;

1: 1) NaOMe / 1) methanol, 2) methanol, reflux, overnight 2: 94 percent / 25percent aqueous KOH / 2 h / Heating 3: 70 percent / dimethylformamide / 1 h / Heating View Scheme

1: 1) NaOMe / 1) methanol, 2) methanol, reflux, overnight 2: 94 percent / 25percent aqueous KOH / 2 h / Heating 3: 70 percent / dimethylformamide / 1 h / Heating 4: 83 percent / oxalylchloride / hexane / 1 h / Heating 5: 100 percent / diethyl ether / 0.5 h / 0 °C View Scheme

sec.-butyllithium in tetrahydrofuran; cyclohexane T=-78°C; Yield given. Yields of byproduct given;

sec.-butyllithium in tetrahydrofuran; cyclohexane T=-78°C; Yield given. Yields of byproduct given;