1: N,N-dimethyl-formamide With trichlorophosphate T=0°C; Vilsmeier-Haack type reaction; 0.5 h; Inert atmosphere; 2: 10-phenyl-1,4-dioxa-7,13-dithia-10-aza-cyclopentadecane T=80°C; Vilsmeier-Haack type reaction; 3 h; Inert atmosphere; 3: With water T=20°C; Vilsmeier-Haack type reaction; Cooling with iceInert atmosphere;

caesium carbonate in ethanol; water T=60°C; 20 h;