in tetrahydrofuran byproducts: NaCl; addn. of tribenzyltin chloride to cerate soln. with stirring (Ar); react., 12h; filtration; evapn.; dissoln. of residue with addn. of activated carbon and Al2O3 (pentane); hot filtration; evapn.; crystn.; filtration; drying (vac.); elem. anal.;

in tetrahydrofuran byproducts: NaCl; addn. of tribenzyltitanium chloride to cerate soln. with stirring (Ar); react., 10h; filtration; evapn.; extn. (pentane); evapn.; storage at -20°C for several d; crystn.; filtration; drying (vac.); elem. anal.;