Heavy Chains: Synthesis, Reactivity and Decomposition of Interpnictogen Chains with Terminal Diaryl Bismuth Fragments.

Abstract

In this work, we report the preparation of multiple interpnictogen chain compounds with three consecutive pnictogen atoms and terminal Ar2 Bi fragments (Ar=Ph, Mes). Symmetrical compounds of the form Ar2 Bi-E(tBu)-Bi2 Ar (1: Ar=Ph, E=P; 2: Ar=Ph, Mes, E=As) as well as ternary interpnictogen compounds of the form Ar2 Bi-E1 (tBu)-E2 tBu2 (Ar=Ph, Mes; 4: E1 =P, E2 =As; 5: E1 =P, E2 =Sb; 6: E1 =As, E2 =P) were prepared. The decomposition in solution at room temperature and under the influence of light was studied for compounds 1-6. The reactivity of 1Ph and 2Ph with the small N-heterocyclic carbene 1,3,4,5-tetramethylimidazol-2-ylidene (Me2 IMe) was also studied. In the case of 1Ph , the formation and consecutive decomposition of Me2 IMe=PtBu (8) was observed in solution. Hence, it was shown that 1Ph can react as a "masked phosphinidene". In the case of 2Ph , no reaction with Me2 IMe was observed. All isolated compounds were analysed by NMR and IR spectroscopy, mass spectrometry, elemental analysis and single-crystal X-ray diffraction.