Tetraalkyl Ammonium

A, acetonitrile and a perchlorate salt such as LiC104 or a tetraalkyl ammonium salt... 

B, acetic acid and an alkali acetate, often plus a tetraalkyl ammonium iodide... 

Anionic Polymerization of Cyclic Siloxanes. The anionic polymerization of cyclosiloxanes can be performed in the presence of a wide variety of strong bases such as hydroxides, alcoholates, or silanolates of alkaH metals (59,68). Commercially, the most important catalyst is potassium silanolate. The activity of the alkaH metal hydroxides increases in the foUowing sequence LiOH < NaOH < KOH < CsOH, which is also the order in which the degree of ionization of thein hydroxides increases (90). Another important class of catalysts is tetraalkyl ammonium, phosphonium hydroxides, and silanolates (91—93). These catalysts undergo thermal degradation when the polymer is heated above the temperature requited (typically >150°C) to decompose the catalyst, giving volatile products and the neutral, thermally stable polymer. 

Low surface energy substrates, such as polyethylene or polypropylene, are generally difficult to bond with adhesives. However, cyanoacrylate-based adhesives can be effectively utilized to bond polyolefins with the use of the proper primer/activa-tor on the surface. Primer materials include tertiary aliphatic and aromatic amines, trialkyl ammonium carboxylate salts, tetraalkyl ammonium salts, phosphines, and organometallic compounds, which are initiators for alkyl cyanoacrylate polymerization [33-36]. The primer is applied as a dilute solution to the polyolefin surface, solvent is allowed to evaporate, and the specimens are assembled with a small amount of the adhesive. With the use of primers, adhesive strength can be so strong that substrate failure occurs during the course of the shear tests, as shown in Fig. 11. 

Reaction of Na2Se and Na2Sc2 with Se in the presence of ethanolic solutions of tetraalkyl-ammonium halides and catalytic amounts of I2 yields dark green or black crystalline polyselenides (jc = 3,5-9) depending on the conditions used and the particular cation selected. Tetraphenylphosphonium salts and crown ether complexes of alkali or alkaline earth cations in dimethylformamide solution can also be used. " )... 

Phase transfer catalysts were used for nucleophilic displacement reactions of activated leaving groups by hydroxyfurazanyl anions. For example, tetrachloro-pyrazine was found to react with hydroxyfurazans in benzene/Na2C03/tetraalkyl-ammonium salts giving products of mono- or disubstitution (Scheme 173) (94MI1). The course of the reaction depends on the ratio of the reactants and the nature of the ammonium salt. 

Die aus Diaryl-, Aryl-benzyl- und Alkyl-aryl-sulfonen zuganglichen Sulfinsauren fallen mit hohen Ausbeuten an, wobei die CBcnzy] vor der CAlkyl- und CAryl-S-Bindung gespalten wird3 (praktische Ausfiihrung s. Lit.4). Bei der Reduktion wird zunachst das Tetraalkyl-ammonium-Kation zum Radikal reduziert, das dann das Elektron auf ein Sulfon-Molekul iibertragt4. 

The reduction ofsec-, and /-butyl bromide, of tnins-1,2-dibromocyclohexane and other vicinal dibromides by low oxidation state iron porphyrins has been used as a mechanistic probe for investigating specific details of electron transfer I .v. 5n2 mechanisms, redox catalysis v.v chemical catalysis and inner sphere v.v outer sphere electron transfer processes7 The reaction of reduced iron porphyrins with alkyl-containing supporting electrolytes used in electrochemistry has also been observed, in which the electrolyte (tetraalkyl ammonium ions) can act as the source of the R group in electrogenerated Fe(Por)R. ... 

The tendency to hydrolyse increases from the chloro to the iodo analogues. Oxohalide technetates are often used as precursors for oxotechnetium complexes, thus making use of their reactivity and good solubility of their tetraalkyl ammonium salts in various organic solvents. Particularly, salts of tetrachloro-oxotechnetate(V) have proven to be such effective starting materials. 

Non-chelated ion-association systems tetraphenylarsonium and tetraalkyl-ammonium salts... 

One of the first results dealing with MS-MS investigations of quats was published by Conboy et al. [36]. Industrially important quats were separated by IC and determined by ion spray MS in the ESI(+) mode. Full scan IC-MS-MS spectra were presented from tetraalkyl ammonium compounds examined. They varied in the alkyl groups, starting at C3H7 and ending at C6H13. 

In analogy, K[BHEt3] can be used to prepare the potassium salt. Metathesis is employed for preparing tetraalkyl ammonium salts. The Li cation in [Li(thp)3]2-... 

The osmotic coefficients calculated from Eq. (9) can be brought into good agreement with solution data up to about 1M for aqueous solutions of alkali (26) and alkaline earth halides, (30) tetraalkyl ammonium halides, T3l) mixed electrolytes, where the Harned coefficients are measured, (32) and electrolyte-non electrolyte mixtures, where Setchenow coefficients are measured. 

The reactions of R NH4 + species show many common features, including significant trends as n is increased from 1 to 4. However, the behaviour of tetraalkyl ammonium ions (n = 4) possesses some characteristics which set them aside from the homologous protonated amines. 

J.B. Green, Liquid chromatography on silica using mobile phases containing tetraalkyl-ammonium hydroxides , J. Chromatogr., 1986, 358, 53. 

By the presence of long alkyl chains in the molecule (tetraalkyl-ammonium or phosphonium cations, esters of phosphoric or sulphuric acid with alcohols with long alkyl chains) ... 

A useful method for the reductive conversion of elemental tellurium into Te anions employs complex hydrides such as sodium or potassium borohydride and tetraalkyl ammonium borohydride as reducing agents. 

In another example, RuCl2(PPh3)3 in [BMIMjCl was shown to be a much less active catalyst than this complex in the ionic liquids [R4N]C1 or [R4N]OH for the aerobic oxidation of alcohol (199). The weaker association of the bulky tetraalkyl-ammonium cation than the planar [BMIM] cation with the anion appears to be the principal reason for the difference. 

The reaction is usually performed with homogeneous basic catalysts such as alkali hydroxides, alkoxides, and tetraalkyl ammonium hydroxide (161,162). The mechanism accepted for this transformation starts with the abstraction by the base catalyst of a proton from the hydroxyl group of the alcohol to generate the alkoxide anion, which reacts with acrylonitrile to form the 3-alkoxypropanenitrile anion. The 3-alkoxypropanenitrile anion abstracts a proton from the catalyst to yield 3-alkoxypropane nitrile. 

W-alkyl- pyridinium tetraalkyl- ammonium tetraalkyl-phosphon ium trialkylsulfonium... 

Trialkyl-borane werden durch Elektrolyse in Nitro-methan mit Tetraalkyl-ammonium-halogeniden als Leitsalz in gutcn Ausbeutcn zu hohercn Nitro-alkanen umgesetzt. So fiihrt die Elektrolyse von Tricyclopentyl-boran zu Cyclopentyl-nitro-methan (150% bez. auf das eingesetzte Organoboran, 50%)1 ... 

A typical battery is composed of poly(acetylene) electrodes which are dipped in propylene carbonate containing tetraalkyl ammonium salt as doping material (Fig 33). By charging poly(acetylene) is doped as represented by Eqs (27) and (28). 

Later studies on the ECF of tetraalkyl ammonium salts, known to be very stable towards electrochemical oxidation, showed that these reactions proceeded similarly to tertiary amines, but with increased formation of gaseous cleavage products [183]. 

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