1: With (2,2,6,6-tetramethylpiperidinyl)MgCl*LiCl; zinc(II) chloride in tetrahydrofuran T=50°C; 3 h; Inert atmosphere; 2: With bromine in tetrahydrofuran; 1,4-dioxane T=-78 - 25°C; Inert atmosphere; regioselective reaction; Further stages;