potassium carbonate in N,N-dimethyl-formamide T=18°C; 42 h;

potassium carbonate in N,N-dimethyl-formamide 24 h; Ambient temperature;

potassium carbonate in N-methyl-acetamide; ethyl acetate

potassium carbonate in ethyl acetate; N,N-dimethyl-formamide

in N,N-dimethyl-formamide

1: potassium carbonate; potassium iodide / ethanol / 24 h / |Reflux 2: trichlorophosphate / 19 h / 100 - 115 °C / |Cooling with ice View Scheme

trichlorophosphate T=100 - 115°C; Vilsmeier-Haack Formylation; 19 h; Cooling with ice; Overall yield = 84.4 percent; Overall yield = 6.5 g;

1: Ba(OH)2·8H2O / methanol / 50 °C / |Inert atmosphere 2: boron trichloride / dichloromethane; hexane / 3.5 h / -78 - 0 °C / |Inert atmosphere View Scheme

AlCl3, aluminium chloride in dichloromethane T=20°C; 5 h;

1: zinc; triphenylphosphine / dichloromethane / 1 h / 20 °C 2: n-butyllithium / tetrahydrofuran / 2 h / -78 °C 3: Pd2(PPh3)2Cl2; copper(l) iodide; triethylamine / 24 h / 20 °C 4: acetic acid / 4 h / 100 °C 5: tin(ll) chloride / ethyl acetate / 10 h / 20 °C 6: hydrogen / ethyl acetate / 5 h / 760.05 Torr 7: sodium cyanoborohydride / methanol / 1 h / 20 °C / pH Ca. 3 8: 1,8-diazabicyclo[5.4.0]undec-7-ene / tetrahydrofuran; N,N-dimethyl-formamide / 2 h / |Reflux 9: water / benzene / 120 °C 10: zinc; acetic acid / water / 5 h / 20 °C 11: boron trichloride / dichloromethane / -10 - 20 °C View Scheme