boron tribromide in dichloromethane T=0 - 20°C; 16 h;

trifluoroacetic acid 48 h; Reflux;

1: triethylamine / dichloromethane / 0 - 20 °C 2: acetonitrile / 0.25 h / 20 °C 3: didodecanoyl peroxide / 1,2-dichloro-ethane / Reflux 4: trifluoroacetic acid / 48 h / Reflux View Scheme

1.1: potassium carbonate / acetone / 12 h / Reflux 2.1: methanol / 12 h / 20 °C / Molecular sieve 2.2: 0.5 h / Cooling with ice 3.1: triethylamine / dichloromethane / 0 - 20 °C 4.1: acetonitrile / 0.25 h / 20 °C 5.1: didodecanoyl peroxide / 1,2-dichloro-ethane / Reflux 6.1: trifluoroacetic acid / 48 h / Reflux View Scheme

1.1: methanol / 12 h / 20 °C / Molecular sieve 1.2: 0.5 h / Cooling with ice 2.1: triethylamine / dichloromethane / 0 - 20 °C 3.1: acetonitrile / 0.25 h / 20 °C 4.1: didodecanoyl peroxide / 1,2-dichloro-ethane / Reflux 5.1: trifluoroacetic acid / 48 h / Reflux View Scheme

1: N-bromosuccinmide; 2-(4-biphenylyl)-5-phenyl-oxazole / tetrachloromethane / 80 °C 2: methanol; ammonia / 2 h / Reflux 3: boron tribromide / 6 h / Reflux View Scheme

1: thionyl chloride / 6 h / Reflux 2: N-bromosuccinmide; 2-(4-biphenylyl)-5-phenyl-oxazole / tetrachloromethane / 80 °C 3: methanol; ammonia / 2 h / Reflux 4: boron tribromide / 6 h / Reflux View Scheme

1: methanol; ammonia / 2 h / Reflux 2: boron tribromide / 6 h / Reflux View Scheme

sodium hydroxide in methanol; N,N-dimethyl-formamide

triethylamine in dichloromethane