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

Abstract

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.

Substitution at boron in molybdaborane frameworks: Synthesis and characterization of isomeric (η5-C5Me5Mo)2B5HnXm (when X=Cl: n=5, 7, 8; m=4, 2, 1 and X=Me: n=6, 7; m=3, 2)

“…From the mass spectral analysis combined with the 11 B NMR spectra both 9 and 10 are formulated as (g 5 40 ppm showed no coupling with hydrogen confirms the BMe environments. All attempts to grow single crystals of 9 and 10 for X-ray structural study failed however, all the spectroscopic data are consistent with the proposed structure as shown in Scheme 1.…”

“…Electrophilic substitution of cage B-H terminal bonds in polyhedral boranes and carboranes have been elegantly demonstrated by Hawthorne [1][2][3][4][5]. Such studies, [6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21] including those leading to peralkylation, perhydroxylation, or perhalogenation, continue to be of significant interest as the persubstitued borane or carborane clusters bear potential applicability in several areas as targets for anti tumor activity [22], weekly coordinating anion [23], components of radioimaging reagent [24], space-controlling drug component, [25].…”

Chemical Hydrogen Storage Using Polyhedral Borane Anions and Aluminum-Ammonia-Borane Complexes

“…The reaction mixture was stirred for 10 minutes and the fine black precipitate formed was filtered and washed with water (10×15 mL) until no evidence of boric acid was visible in washings by 11 B NMR. The precipitate was further washed with ethanol (5 mL) and dried under vacuum at 100 ºC for 12 h to give a fine black powder (0.037 g, 95%).…”

“…The production of hydrogen vs. time was measured using a mercury manometer. On completion of the reaction, the pressure was released and the reaction mixture was analyzed by 11 B NMR. The NMR spectrum showed a single peak at δ 16.7 ppm corresponding to potassium metaborate, indicating that the hydrolysis reaction was complete.…”

“…The Erying plot of ln(k/T) vs. 1/T for the various borane anions is shown in Figure 5 12 was prepared by following literature method, [11] by reacting closo-Cs 2 B 12 H 12 with hydrogen peroxide at elevated temperature. Closo-Cs 2 B 10 Cl 10 was synthesized according to literature methods [12] by reacting (NH 4 ) 2 B 10 H 10 with chlorine gas and ion exchanging the resulting (NH 4 ) 2 B 10 Cl 10 with CsCl.…”