Zwölffache Funktionalisierung eines Ikosaeders durch vollständige Veresterung von [B12(OH)12]2−: 12(12)-Closomere

Catalytic hydroxylation of [closo-B12H12](2-)-adaptation of the Periana reaction to a polyhedral borane

Per-B-hydroxylation of a polyhedral borane anion has been demonstrated by the catalytic hydroxylation of icosahedral [closo-B(12)H(12)](2-) using soft electrophiles such as platinum group metal catalysts or iodine cation. A new route to [closo-B(12)(OH)(12)](2-) from [closo-B(12)H(12)](2-) without the use of H(2)O(2) oxidant provides an alternative hydroxylation process.

An Improved Method for the Synthesis of [closo-B12(OH)12]-2

The dicesium salt of the icosahedral borane anion dodecahydroxy-closo-dodecaborate(2-), closo-Cs(2)B(12)(OH)(12), Cs(2)4, was prepared using an improved synthetic pathway. Heating cesium dodecahydro-closo-dodecaborate, closo-Cs(2)B(12)H(12), Cs(2)1, with 30% hydrogen peroxide added in successive increments at 105-110 degrees C provided Cs(2)4 in 95% yield. Reaction progress was monitored using (1)H-decoupled (11)B NMR while (17)O NMR provides the most reliable way to detect the presence of peroxides in the reaction solution. The reaction may be safely increased in scale to afford Cs(2)4 in multigram quantities.