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

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