Synthesis and characterization of a Bi10O8(OAr)16 oxo-cluster supported by p-tert-butylcalix[5]arene ligands

Abstract

Reaction of a non-dried monobenzylated [^tBuC5(OBn)(OH)₄] ligand with excess of Bi[N(SiMe₃)₂]₃ yields a mixture of the dimeric complex 1 [Bi{^tBuC5(OBn)(OH)}]₂ in 12% yield and complex 2 [Bi₁₀O₈{^tBuC5(OBn)(OH)}₄] in 48% yield. The highly symmetric complex 2 features a Bi₁₀O₈(OAr)₁₆ central core with tetra-, hexa- and heptacoordinated bismuth(III) centers, and (μ2)–(μ4) bridging oxygen atoms all arranged in a I4 symmetrical pattern. Cluster 2 represents the largest bismuth oxo-cluster supported by calix[n]arene ligands reported to date.