1,4-PHENYLENE-BRIDGED 1,3,2,4,6-THIAPHOSPHATRIAZINYL AND 1,3,2,4,6-SELENAPHOSPHATRIAZINYL DIRADICALS - PREPARATION, SPIN DISTRIBUTIONS, AND SOLID-STATE STRUCTURES

The 1,4-phenylene-bridged bis(1,3,2,4,6-thiaphosphatriazine) and bis(1,3,2,4,6-selenaphosphatriazine) compounds (ClEN3PPh2C)C6H4(CPPh2N3ECl) (E = S, Se) have been prepared by the reactions of 1,4-phenylenebis(phosphimidoylamidine), (Me3Si)2NPPh2(Me3SiN)CC6H4C(NSiMe3)PPh2N(SiMe3)2, with SCl2 and SeCl4. Reduction of these E-chloro derivatives with triphenylantimony affords the corresponding bis(thiaphosphatriazinyl) and bis(selenaphosphatriazinyl) diradicals, (EN3PPh2C)C6H4(CPPh2N3E) (E = S, Se). The ESR spectra of these materials in CH2Cl2 are consistent with noninteracting radicals, an observation suggested to arise from association of radicals through a single terminus. The solid-state structure of the selenium compound, (SeN3PPh2C)C6H4(CPPh2N3Se), reveals association through both termini to produce a centrosymmetric dimer. Association occurs through Se-N rather than Se-Se linkages. Crystals of C32H24N6P2Se2.2CH3CN belong to the rhombohedral space group R3BAR; fw = 794.6, a = 34.431 (12) angstrom, c = 17.513 (4) angstrom, and Z = 9.