1: With N,N,N',N,-tetramethylethylenediamine; tert.-butyl lithium in diethyl ether; pentane T=-45 - 0°C; 4.25 h; Inert atmosphere; 2: With 1,2-dibromo-1,1,2,2-tetrachloroethane in tetrahydrofuran; diethyl ether; pentane T=20°C; 17 h; Inert atmosphere; enantioselective reaction;