Hydroxide tetraalkyl ammonium

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

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. 

Guanine 9-Alkylguanines Tetraalkyl ammonium hydroxide/fusion 63JOC2087... 

Yang, J., Mei, S., and Ferreira, J.M.R, Hydrothermal synthesis of nanosized titania powders Influence of tetraalkyl ammonium hydroxides on particle characteristics, J. Am. Ceram. Soc., 84, 1696, 2001. 

It is possible to measure and compare the acidities of compounds that are not acidic enough to be ionized in water by using a more basic medium. Stewart and O Donnell established the H scale for solutions of tetraalkyl-ammonium hydroxide in sulfolane, DMSO-water, pyridine-water, and water. In essence, the H scale extends upward the range for which pfCg values can be measured (which is effectively from 0 to 14 in aqueous solution) by another 12 pK units of basicity. A number of workers have modified the Hammett approach to acidity functions. In particular, Cox and Yates proposed the excess acidity function, X, which represents the difference between the acidity observed for a system and the acidity that would be observed if the system were ideal. In this approach, the activity coefficient ratio in equation 7.27 is taken to be the product of a coefficient m times the activity coefficient ratio, X, for a hypothetical standard base, B. Here m is a constant characteristic of each base, while X is a constant characteristic of the med-... 

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. 

Induction periods of various lengths have been reported for anionic and cationic polymerizations of formaldehyde. It is apparent that the compound that is added as initiator is rarely the actual initiator. Tetraalkyl ammonium acetate used for the potymerization of formaldehyde is a slow initiator but capable of initiating formaldehyde polymerization. Methanol, other alcohols or water, always present in the polymerization mixture, are responsible for the high rates of polymerization. They act as efficient chain transfer agents and alkoxide or hydroxide ions are the actual initiators they initiate by a factor of several powers of ten more efficiently than acetate. 

The use of tetraalkyl ammonium as counterions was explored but remains limited due to the low thermal stability of the compound. As an example, didodecyldimethylammonium hydroxide was employed by Maitre et to polymerize... 

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