Tetramethylanunonium

In this case tetramethylanunonium hydroxide is preferred to sodium or potassium hydroxide as the base. Triton B is less satisfactory. ... 

Acetic acid (2 mL) was added to a stirred suspension of tetramethylanunonium triace-toxyborohydride (1.54 g, 5.85 nunol) in acetonitrile (2 mL) at room temperature. The mixture was stirred at room temperature for 30 min and then cooled to -40 °C. The P-hydroxyketone (300 mg, 0.731 mmol) in acetonitrile (2 mL) was added dropwise at this temperature. A solution of camphorsulfonic acid (85 mg, 0.366 mmol) in a mixture of acetic acid acetonitrile (1 1,4 mL) was added, and the mixture was allowed to warm to -22 °C over 18 h. The mixture was poured into saturated aqueous NaHCOs (50 mL). A saturated aqueous solution of sodium potassium tartrate (50 mL) was added, followed by ether (100 mL), and the mixture was stirred vigorously at room temperature for 8 h. The layers were separated, and the aqueous layer was extracted with EtOAc (3 x 50 mL). The combined organic extracts were washed with water (50 mL), brine (50 mL), and dried (MgSO4). The solvent was removed under vacuum to afford 300 mg (99.5%, dr >97 3) of the anz/-l,3-diol as a colorless oil. 

Some bases, such as sodium hydroxide and tetramethylanunonium hydroxide, are used for sample dissolution, as are some reagents that are not acids or bases, like hydrogen peroxide. The chemical literature contains sample dissolution procedures for virtually every type of material kuown and should be consulted. For elements and inorganic compounds, the CRC Handbook of Chemistry and Physics gives guidelines for dissolution in the tables of physical properties of inorganic compounds. 

Note. Among the products of the persulphate-initiated oxidation of acrylonitrile, formaldehyde, cyanide and glycolonitrile did not interfere with the wave in 0-02 M tetramethylanunonium iodide. Excess of persulphate reacts with the added hydroquinone. When the concentration of acrylonitrile is determined from a measurement of the current at — 1 -5 V and — 2-0 V, potassium ions in the sample interfered and thus a numerical correction based on a known concentration of potassium ions was introduced. 

Berr, S.S., Coleman, M.J., Jones, R.R.M., Johnson, J.S., Jr. Small-angle neutron scattering study of the structural effects of substitution of tetramethylanunonium for sodium as the counterion in dodecyl sulfate micelles. J. Phys. Chem. 1986, 90(24), 6492-6499. 

The diemicals used in the preparation of the titanates were tetraisopippyl dtanate, an aqueous solution of NaOH, a solution of tetramethylanunonium hydroxide in methanol, A1(N03)3 9H20, tetrtqnropylanunonium chloride, and teti ntyl ammonium chloride. These chemicals were mixed in an tq ropriate manner to produce in most cases a white precipitate. In some cases, depending on the solution composition, a ciystaUine titanate formed at room tenq)erature. 

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