in tetrahydrofuran; diethyl ether under Ar atm. soln. Et3SnOAc in Et2O/THF (1:1) was added at room temp. to soln. GeCl2*dioxane in Et2O/THF and stirred for 30 min; solvent was distilled off, residue was evapd. at 100°C/1 Torr, residue was treated with ether, ppt. was filtered off, washed, and dried in vacuo; elem. anal.;