hydrogenchloride; water in tetrahydrofuran 1 h;

1: With chloro-trimethyl-silane; lithium hexamethyldisilazane in tetrahydrofuran T=-78 - 0°C; 0.5 h; 2: With phenyltrimethylammonium tribromide in tetrahydrofuran T=0°C; 0.5 h;