1: With N,N,N',N'-tetramethyl-7,8-dihydro-6H-dipyrido[1,2-a;2',1'-c][1,4] diazepine-2,12-diamine in N,N-dimethyl-formamide T=20°C; 72 h; Inert atmosphereGloveboxUV-irradiation; 2: With hydrogenchloride in water; N,N-dimethyl-formamide T=0°C; pH=< 3; Inert atmosphere; chemoselective reaction;

N,N,N',N',N'',N''-hexamethylphosphoric triamide; samarium diiodide in tetrahydrofuran Ambient temperature;