1: tert-butyl-(2,4-dichloro-phenoxy)-dimethyl-silane With n-butyllithium in tetrahydrofuran; hexane T=-78°C; 0.5 h; 2: N,N-dimethyl-formamide in tetrahydrofuran; hexane 1 h; 3: With hydrogenchloride; water in tetrahydrofuran; hexane T=20°C;