in carbon disulfide under N2, dropwise addn. of a Br2/CS2 soln. to a vigorously stirred soln. of P4/CS2 reaction of P4 with ICl (molar ratio (1.75:1.5), further Products: PCl3, PCl2I, PClI2, PI3; not isolated, identified by 31P-NMR spectroscopy;