chlorine in tetrachloromethane; hexane byproducts: C4(C6H5)4PCl; N2-atmosphere; addn. of Cl2 soln. (in hexane) to soln. of Re-complex (inCCl4) at -10°C; solvent removal (25°C, 15 mmHg, sublimation (50°C, 0.01 mmHg);

bromine in tetrachloromethane; hexane byproducts: C4(C6H5)4PBr; N2-atmosphere; addn. of Br2 soln. (in hexane) to soln. of Re-complex (inCCl4) at -10°C; solvent removal (25°C, 15 mmHg, sublimation (50°C, 0.01 mmHg);