N-bromosuccinmide in tetrahydrofuran; acetic acid T=60°C; 0.5 h;

tetraphosphorus decasulfide in toluene Heating;

in N,N-dimethyl-formamide T=150°C; 1 h; Schlenk techniqueInert atmosphere;

1.1: n-BuLi / diethyl ether / 1 h / -10 °C 1.2: 90 percent / diethyl ether / 1 h / -10 - 20 °C 2.1: N,N,N',N'-tetramethylethylenediamine; n-BuLi / diethyl ether / 1 h / -65 °C 2.2: ZnCl2 / diethyl ether; tetrahydrofuran / 1 h / 25 °C 2.3: 32 percent / Pd(PPh3)4 / diethyl ether; tetrahydrofuran / 7 h / 50 °C 3.1: 82 percent / NBS / tetrahydrofuran; acetic acid / 0.5 h / 60 °C View Scheme

1.1: N,N,N',N'-tetramethylethylenediamine; n-BuLi / diethyl ether / 1 h / -65 °C 1.2: ZnCl2 / diethyl ether; tetrahydrofuran / 1 h / 25 °C 1.3: 32 percent / Pd(PPh3)4 / diethyl ether; tetrahydrofuran / 7 h / 50 °C 2.1: 82 percent / NBS / tetrahydrofuran; acetic acid / 0.5 h / 60 °C View Scheme

hydrogenchloride; chloroform; hydrogen sulfide; tin(IV) chloride

tetrakis(triphenylphosphine) palladium(0) in N,N-dimethyl-formamide T=90°C;