1.1: 97 percent / p-toluenesulfonic acid / benzene / 16 h / Heating 2.1: sec-butyllithium / tetrahydrofuran; cyclohexane / 4 h / -70 - 20 °C 2.2: tetrahydrofuran; cyclohexane / 2 h / 20 °C 3.1: 0.31 g / boron trifluoride etherate; hydroquinone / tetrahydrofuran / 0.25 h / 20 °C View Scheme

2: brown MnO2 / CHCl3 / 26 h / Heating 3: anhydrous Na2SO4, trifluoroacetic acid / CH2Cl2 / 0.92 h / Heating View Scheme

2: brown MnO2 / CHCl3 / 26 h / Heating View Scheme

1: 49 percent / n-BuLi / tetrahydrofuran; hexane / 10 h / Ambient temperature 2: 23 percent / LDA/N-BuLi / tetrahydrofuran; hexane / 10 h / -78 °C 3: 35 percent / hydroxylamine hydrochloride/NaOAc / 1,2-dichloro-benzene / 14 h / Heating 4: NaOH / H2O; ethanol / 2 h / Heating 5: 98 percent / quinoline / 1 h / Heating View Scheme

aluminium trichloride; sodium azide in tetrahydrofuran Heating;

1.1: 65 percent / t-BuOK / tetrahydrofuran 2.1: LDA / tetrahydrofuran / 1 h / -78 °C 2.2: tetrahydrofuran / -78 - -10 °C 2.3: 76 percent / NH2OH*HCl; AcONa / 1,2-dichloro-benzene / 8 h / Heating View Scheme

1: 97 percent / triphenylphosphine / CH2Cl2 / 5 h / 0 °C 2: 37 percent / n-butyllithium / tetrahydrofuran; hexane / -78 - 20 °C View Scheme

1: 98 percent / benzene / a.) 0 deg C, 15 min, b.) r. t., overnight, c.) 19 h, reflux 2: 72 percent / p-TsOH / benzene / 1 h / Heating 3: 62 percent / K2CO3 / ethanol / 15 h / Heating 4: KtBuO / tetrahydrofuran / 0.5 h / 0 °C 5: 69 percent / tetrahydrofuran / 0.5 h / Ambient temperature; pH 4 (aq. buffer solution citric acid - sodium acetate) 6: 65 percent / aq. 50percent HOAc / 15 h / Ambient temperature View Scheme