143-66-8

white powder

As reagent for determination of potassium, ammonium, rubidium and cesium ions: Barnard, Buechl, Chemist-Analyst 48, 44, 49 (1959); Montequi, Serrano, An. R. Acad. Farm. 26, 107 (1960).

Determination of potassium, ammonium, rubidium, and cesium.

Sodium Tetraphenylboroate is a salt that is commonly used in inorganic and organometallic chemistry as a precipitating agent. Sodium Tetraphenylboroate is also utilized for the preparation of N-acylam monium salts and in coordination chemistry due to their favourable solubility in nonpolar sovlents and their crystallinity.

Dissolve the borate in dry MeOH and add dry Et2O. Collect the solid and dry it in a vacuum at 80o/2mm for 4hours. It can also be extracted (Soxhlet) using CHCl3, and it crystallises from CHCl3 as snow-white needles. It is freely soluble in H2O, Me2CO but insoluble in pet ether and Et2O. An aqueous solution has pH  5 and can be stored for days at 25 or lower, and for 5 days at 45o without deterioration. Its solubility in polar solvents increases with decrease in temperature [Wittig & Raff Justus Liebigs Ann Chem 573 204 1950]. The salt can also be recrystallised from acetone/hexane or CHCl3, or from Et2O/cyclohexane (3:2) by warming the solution to precipitate the compound. Dry it in a vacuum at 80o. It dissolves in Me2CO at 50-60o to give a clear solution. After standing at this temperature for 10minutes the mixture is filtered rapidly through a pre-heated Büchner funnel, cooled and the crystals are collected and dried in a vacuum desiccator at room temperature for 3days [Abraham et al. J Chem Soc, Faraday Trans 1 80 489 1984]. If the product gives a turbid aqueous solution, the turbidity can be removed by treating with freshly prepared alumina gel and filtering. [Beilstein 16 IV 1624.]