trichlorophosphate in acetonitrile T=0 - 20°C; Vilsmeier-Haack Formylation; Inert atmosphere;

1: 91 percent / boron trichloride / CH2Cl2 / -78 - 20 °C 2: 75 percent / POCl3 / acetonitrile / 0 - 25 °C View Scheme

1: potassium carbonate / acetone / 20 °C / |Molecular sieve 2: boron trichloride / dichloromethane; n-heptane / 1 h / -78 - 20 °C 3: trichlorophosphate / acetonitrile / 0 - 20 °C / |Inert atmosphere View Scheme

(i) HCl, (ii) H2O; Multistep reaction;

1: palladium 10 on activated carbon; hydrogen / ethyl acetate; ethanol / 4 h / 20 °C 2: pyridine / dichloromethane / 0 - 20 °C 3: tetrakis(triphenylphosphine) palladium(0); lithium chloride / tetrahydrofuran / 7 h / |Inert atmosphere; |Reflux 4: boron tribromide / dichloromethane / -78 - 0 °C View Scheme

palladium 10 on activated carbon; hydrogen in ethanol; ethyl acetate T=20°C; 4 h;

1: Zn-Hg, aq. HCl 2: aq. KOH View Scheme