N-chloro-succinimide; acetic acid in benzene 1 h; Heating;

N-chloro-succinimide; perchloric acid in tetrachloromethane 24 h; Ambient temperature; Yield given. Yields of byproduct given;

potassium hydroxide; hydrazine hydrate

ueber 2-Brommethyl-5-chlor-thiophen und N-<5-Chlor-<2>thienylmethyl>-hexamethylentetraminium-bromid dargestellt;

1: 2-methyl-5-chlorothiophene With PdCl2(MeCN)2; caesium carbonate; 2-(dicyclohexylphosphino)-2',4',6'-tri-i-propyl-1,1’-biphenyl in N,N-dimethyl-formamide T=20°C; Sonogashira coupling; 0.5 h; Inert atmosphere; 2: (Tri-iso-propylsilyl)acetylene in N,N-dimethyl-formamide T=100°C; Sonogashira coupling; 18 h; Inert atmosphere;

1: 2-methyl-5-chlorothiophene With PdCl2(MeCN)2; caesium carbonate; 2-(dicyclohexylphosphino)-2',4',6'-tri-i-propyl-1,1’-biphenyl in 1,4-dioxane T=20°C; Sonogashira coupling; 0.5 h; Inert atmosphere; 2: (Tri-iso-propylsilyl)acetylene in 1,4-dioxane T=100°C; Sonogashira coupling; 17 h; Inert atmosphere;

1.1: AlCl3 / CH2Cl2 / 0.5 h / 0 °C 1.2: 78 percent / CH2Cl2 / 9 h / 0 - 20 °C 2.1: 53 percent / Br2 / CHCl3 / 12 h 3.1: 65 percent / Na2S / ethanol / 1 h / 20 °C 4.1: 70 percent / TiCl4; Zn powder / tetrahydrofuran / 48 h / 20 °C View Scheme

1: ueber 2-Brommethyl-5-chlor-thiophen und N-<5-Chlor-<2>thienylmethyl>-hexamethylentetraminium-bromid dargestellt View Scheme