in neat (no solvent) refluxed (4 h); distd. (vac.);

in gas vaporization of Ge (alumina-coated tungsten crucible, 1200-1300°C, 5E-3 Torr), introduction into reaction flask (cooled with liq. N2 during Ge vaporization) together with vapor of org. halide, warming to room temp., standing for 1.5 h; GC-MS, GLC;

copper under dried abs. N2; fine powdered Ge and Cu-Powder divided among glass wool in a quartz tube; addn. of CH2Br2 (1 drop/s) during heating in a oven until 310°C; reaction finished after 4 h; summarizing in cooling trap at -78°C; removing of excess CH2Br2 at 25°C and 1 atm; fractioned distn. under vac.; crystn. of (CH2GeBr2)2; elem. anal.; NMR; IR; mass spectroscopy;

in neat (no solvent) boiled (5 h, 115-120°C); vac. distd., GLC, (1)H-NMR;