Tetra­butyl­ammonium 2-[2,5-dimethyl-3-(4-nitro­phen­yl)-2,3-dihydro-1,2,4-oxadiazo­lium-4-yl]nona­hydro-closo-deca­borate

The title ionic compound, C₁₆H₃₆N⁺·C₁₀H₂₀B₁₀N₃O₃^-, consists of a tetra­butyl­ammonium cation and a closo-deca­borate cluster anion, which is bound to the substituted 2,3-dihydro-1,2,4-oxadiazole ring through a B-N bond [1.540 (2) Å]. The distances between connected B atoms in the deca­borate cluster range from 1.689 (2) to 1.844 (2) Å. The 2,3-dihydro-1,2,4-oxadiazole ring adopts an envelope conformation with the N atom as the flap atom.