in further solvent(s) byproducts: SbCl3; treatment of chlorophosphazene in CHCl2CHCl2 with SbF3, stepwise addn. of SbCl5 to refluxing soln. (stirring), refluxing for 40-80 min (GLC-control); decantation, evapn. (vac.), repeated extn. and evapn. (pentane, then pentane or CH2Cl2), gas chromy., recrystn. (pentane, -80°C); elem. anal.;