(i) (diazotization), BF3, (ii) (heating); Multistep reaction;

1: With hydrogenchloride; sodium nitrite in water T=0°C; 0.5 h; 2: With CuCl2*H2O; sulfur dioxide; acetic acid T=25°C; 1 h;

1: 2-(4-biphenylyl)-5-phenyl-oxazole; tert.-butylnitrite / acetonitrile / 4 h / 20 °C 2: 5 palladium on charcoal; hydrogen / methanol / 4 h / 20 °C / 760.05 Torr View Scheme

1.1: N-bromosuccinmide / ethyl acetate / 22 °C 2.1: Zn(ClO4)2-2H2O / toluene / 20 - 80 °C / Molecular sieve 2.2: 30 °C / 750.08 Torr 3.1: sodium hydrogencarbonate / ethyl acetate 3.2: 20 °C 3.3: 80 °C / Inert atmosphere 4.1: dichloro bis(acetonitrile) palladium(II) / acetonitrile / 20 - 80 °C / Inert atmosphere View Scheme

1: 1.) 36percent hydrochloric acid, sodium nitrite; 2.) SO2, CuCl2 / 1.) water, -5 deg C, 120 min; 2.) water, glacial acetic acid, r.t., 10 min 2: 1.) 20percent K2CO3, water, ethanol; 2.) 30percent hydrochloric acid / 1.) 50 deg C, 30 min; 2.) water, 0 deg C 3: 1.) iron powder, 30percent hydrochloric acid; 2.) Bechamp-suspension / 1.) water, reflux, 30 min; 2.) reflux, 120 min 4: 82.1 percent / hydrogen, Na2CO3 / 10percent Pd/C / H2O / 16 h View Scheme

1: (i) NaNO2, aq. HCl, (ii) KI, I2 2: (i) Cu, (ii) polyphosphoric acid, (iii) SnCl2, aq. HCl View Scheme

暂无反应条件数据

1.1: N-bromosuccinmide / ethyl acetate / 22 °C 2.1: Zn(ClO4)2-2H2O / toluene / 20 - 80 °C / Molecular sieve 2.2: 30 °C / 750.08 Torr 3.1: sodium hydrogencarbonate / ethyl acetate 3.2: 20 °C 3.3: 80 °C / Inert atmosphere 4.1: dichloro bis(acetonitrile) palladium(II) / acetonitrile / 20 - 80 °C / Inert atmosphere 5.1: triethylamine / dichloromethane / 0 - 20 °C 6.1: hydrogen / 5 palladium on charcoal / tetrahydrofuran / 96 h / 50 °C / 2250.23 - 3000.3 Torr / autoclave; Inert atmosphere View Scheme

tert.-butylnitrite; 2-(4-biphenylyl)-5-phenyl-oxazole in acetonitrile T=20°C; 4 h;

1: With bromine; acetic acid in chloroform T=0 - 20°C; 2 h; 2: With sodium hydroxide in chloroform; water T=0°C; pH=8.0 - 9.0;