1.1: tetra-n-butylammonium nitrate / dichloromethane / -5 °C 1.2: -5 - 20 °C 2.1: trichlorophosphate / 1 h / |Reflux View Scheme

1.1: oxalyl dichloride; N,N-dimethyl-formamide / 1,2-dichloro-ethane 2.1: n-butyllithium / tetrahydrofuran; hexane / 2 h / -70 °C / |Inert atmosphere; |Large scale 2.2: 19.3 h / -70 - 20 °C / |Inert atmosphere; |Large scale 3.1: tetrakis(triphenylphosphine) palladium(0) / N,N-dimethyl-formamide / 40 h / 95 °C / |Inert atmosphere; |Large scale View Scheme

1: 72 percent / oxalyl chloride / 1,2-dichloro-ethane; dimethylformamide 2: BuLi; I2 View Scheme

oxalyl dichloride; N,N-dimethyl-formamide in dichloromethane; 1,2-dichloro-ethane 6 h; Reflux;

in N-methyl-acetamide; dichloromethane

1: POCl3 2: 76 percent / Zn, AcOH / 5 h / Ambient temperature View Scheme

1: With tetra-n-butylammonium nitrate in dichloromethane T=-5°C; 2: With trifluoroacetic anhydride in dichloromethane T=-5 - 20°C;

1: With phosphorus oxytribromide T=69 - 100°C; 2 h; 2: With sodium hydroxide in water pH=10 - 11;