iron; acetic acid in ethanol 1 h; Reflux;

1: 1.) sodium nitrite, 5N HCl; 2.) aq. KI / 1.) 0-10 deg C; 2.) RT, 30 min 2: 69 percent / SnCl2, conc. HCl / ethanol / 0.25 h / 50 - 60 °C View Scheme

1: 3N KOH / 24 h / Heating 2: 1.) sodium nitrite, 5N HCl; 2.) aq. KI / 1.) 0-10 deg C; 2.) RT, 30 min 3: 69 percent / SnCl2, conc. HCl / ethanol / 0.25 h / 50 - 60 °C View Scheme

1: HNO3 / 8 min below 0 deg C, 8 min, RT. 2: 3N KOH / 24 h / Heating 3: 1.) sodium nitrite, 5N HCl; 2.) aq. KI / 1.) 0-10 deg C; 2.) RT, 30 min 4: 69 percent / SnCl2, conc. HCl / ethanol / 0.25 h / 50 - 60 °C View Scheme

1.1: dihydrogen peroxide; hydrogen bromide / methanol; water / 1.5 h / 0 - 20 °C 2.1: boron trifluoride diethyl etherate / tetrahydrofuran / 0.5 h / -30 °C 2.2: 1.25 h / -30 - -5 °C 2.3: 1.3 h / 20 °C 3.1: acetic acid; iron / ethanol / 1.3 h / 100 °C View Scheme

1: 72 percent / pyridine / 3 h / 0-10 deg C 2: CuI, Et3N / Pd(PPh3)2Cl2 / 60 °C 3: NaOEt / ethanol / Heating View Scheme

potassium tert-butylate in N,N-dimethyl acetamide T=120°C; 24 h; Schlenk techniqueInert atmosphere;