Synthesis and crystal structures of (CF3)2As–NPPh3, [Os3(CO)11{(CF3)2AsNPPh3}] and [Os3(µ-H)2(CO)9{(CF3)2AsNPPh3}]

Abstract

Bis(trifluoromethyl)arsinous azide (CF₃)₂AsN₃ undergoes a Staudinger reaction with PPh₃ to give the arsinophosphazene (CF₃)₂As–NPPh₃ which reacts with [Os₃(CO)₁₁(MeCN)] and [Os₃(µ-H)₂(CO)₁₀] to give [Os₃(CO)₁₁{(CF₃)₂AsNPPh₃}]1 and [Os₃(µ-H)₂(CO)₉{(CF₃)₂AsNPPh₃}]2 respectively. Single-crystal X-ray structural studies show that upon complexation (CF₃)₂As–NPPh₃ assumes a highly delocalized electronic structure over the unsymmetrical As–NP segment with the As–N bond distance assuming that of an AsN double bond. These two complexes represent the first examples of neutral compounds containing a highly delocalized AsNP non-linear structure.