tri-n-butyl-tin hydride; triethylamine in acetonitrile 1 h; Irradiation;

1,8-DMP; 2,3-dihydro-2-(2-hydroxyphenyl)-1,3-dimethyl-1H-benzimidazole in acetonitrile T=20°C; 0.5 h; Inert atmosphereIrradiation;

triethylamine in acetonitrile 1 h; Irradiation;

1.1: sodium hydroxide / ethanol; water / 20 °C / Inert atmosphere 1.2: Inert atmosphere 2.1: thionyl chloride / toluene / 2 h / Inert atmosphere; Reflux 3.1: dichloromethane / 20 °C / Inert atmosphere 4.1: N,N,N',N,-tetramethylethylenediamine; tert.-butyl lithium / tetrahydrofuran / -78 °C / Inert atmosphere 4.2: 20 °C / Inert atmosphere 4.3: 20 °C / Inert atmosphere 5.1: manganese(IV) oxide; acetic acid / dichloromethane / 20 °C / Inert atmosphere 6.1: tetrahydrofuran / -78 °C / Inert atmosphere 6.2: Inert atmosphere 7.1: trifluoroacetic acid / dichloromethane / 4 h / 20 °C / Inert atmosphere View Scheme

1: With sodium hydroxide in ethanol; water T=20°C; Inert atmosphere; 2: With hydrogenchloride in water Inert atmosphere;