in pentane byproducts: PbCl2; all manipulations without O2 and moisture; Pb compd. dissolved in pentane and soln. of SnCl4 added at 0°C, allowed to warm to room temp.,stirred for 30 min; filtered, solvent removed in vac.;

in pentane byproducts: SnCl3; all manipulations without O2 and moisture; soln. of SnCl4 added dropwiseto excess of soln. of Pb compd. at 0°C by stirring; filtered, solvent removed in vac.; mixt. of mono- and disubstituted compds. in 1:1-1:4 ratio (depending on amt. of SnCl4) , which could not be separated by distn. or sublimation;

in pentane all manipulations without O2 and moisture; soln. of SnCl4 added to excess of soln. of Pb compd. at 0°C; filtered, solvent removed in vac.; mixt. of mono- and disubstituted compds. in 1:1-1:4 ratio (depending on amt. of SnCl4) , which could not be separated neither by crystn. nor by distn. or sublimation;