in pentane to a soln. of K2(t-BuP)2*0.5THF a soln. of Et2GeCl2 is dropwise added with stirring at -78°C over 20 min, further stirring for 15 min (Ar); mixt. is filtered in the cold, residue is washed with pentane, the filtrates are collected and the solvent is evapd. (aspirator), ppt. is driedat 1E-3 Torr (90 min) and recrystd. from n-pentane, elem. anal.;