iodine; magnesium in tetrahydrofuran

1: copper(l) iodide; bis-triphenylphosphine-palladium(II) chloride; diisopropylamine / N,N-dimethyl-formamide / 5 h / 20 °C / Inert atmosphere 2: potassium carbonate; L-proline; copper(I) bromide / dimethyl sulfoxide / 3 h / 100 °C / Inert atmosphere View Scheme

1: 1,2-difluoro-4-iodobenzene With lithium diisopropyl amide in tetrahydrofuran T=-78°C; 1 h; Inert atmosphere; 2: carbon dioxide in tetrahydrofuran T=-78 - 25°C; Inert atmosphere; 3: With hydrogenchloride in water pH=2;