Synthesis of arsenic-rich As_n ligand complexes from yellow arsenic

Abstract

The reaction of [{η⁵-Cp'''Co}₂{μ,η^4:4-toluene}] with yellow arsenic yields the arsenic-rich As _<i>n</i> ligand complexes [{Cp'''Co(μ,η^2:2-As₂)}₂] (<b>1</b>), [(Cp'''Co)₄(μ₄,η^4:4:2:2:1:1-As₁₀)] (<b>2</b>) and [(Cp'''Co)₃(μ₃,η^4:4:2:1-As₁₂)] (<b>3</b>), which were comprehensively characterized. The molecular structure of <b>1</b> show a triple-decker complex with two As₂ units forming the middle-deck; compound <b>2</b> contains an all-arsenic As₁₀ analogue of dihydrofulvalene in the molecular structure. The As₁₂ ligand in <b>3</b> represents the largest As _<i>n</i> ligand complex reported so far.