1.1: potassium carbonate / tetrahydrofuran / 12 h / 20 °C 2.1: phosphorous pentoxide; dimethylformaldehyde dimethyl acetal / chloroform / 8 h / 20 °C / |Inert atmosphere 3.1: palladium diacetate; silver(l) oxide; potassium acetate / N,N-dimethyl-formamide / 110 °C 4.1: lithium aluminium tetrahydride / diethyl ether / 3 h / 20 °C / |Cooling with ice 4.2: 0.5 h / |Cooling with ice 5.1: pyridine; trimethylsilyl iodide / sulfolane / 20 h / 70 °C / |Inert atmosphere 6.1: anhydrous iron chloride; tert.-butylhydroperoxide; pyridine-2,6-dicarboxylate N-oxide / water; 1,1-dimethylpropan-1-ol / 8 h / 20 °C / |Cooling with ice View Scheme