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Tertiary amine cation

Ingemann, S. Hammerum, S. Derrick, P.J. Secondary Hydrogen Isotope Effects on Simple Cleavage Reactions in the Gas Phase The a-Cleavage of Tertiary Amine Cation Radicals. J. Am. Chem. Soc. 1988, 770,3869-3873. [Pg.63]

Program GRID works in very much the same way, but the objective is to obtain chemically specific information about the molecule. An electrostatic potential does not normally allow one to differentiate between favorable binding sites for a primary or a secondary or a tertiary amine cation, or tetramethyl ammonium or... [Pg.5]

Table 7. Relative rates of deprotonation of the a-substituted tertiary amine cation radical from product distribution and laser spectroscopic studies. ... Table 7. Relative rates of deprotonation of the a-substituted tertiary amine cation radical from product distribution and laser spectroscopic studies. ...
The failure of tertiary (AI,IV-dimethylaminoalkyl)arenes and stilbenes to undergo intramolecular addition may reflect structural differences between inter- vs. intramolecular exciplexes. Polar solvents are generally required for the observation of in-termolecular addition reactions of tertiary amine exciplexes. Equilibration between solvent-separated and radical ion pairs may be necessary in order to achieve an appropriate reaction trajectory for a-C-H proton transfer. In the case of intramolecular exciplexes with short chain linkers, electron transfer in polar solvents may occur in extended geometries which are inappropriate for proton transfer and chain folding may not compete effectively with exciplex decay. The exceptions to these generalizations, benzene and styrene, form more localized anion radicals which undergo both inter- and intramolecular reactions with tertiary amine cation radicals in nonpolar solvents. [Pg.24]

The acryHc weak base resias are syathesized from copolymers similar to those used for the manufacture of weak acid cation-exchange resias. For example, uader appropriate temperature and pressure conditions, a weak acid resia reacts with a polyfuactioaal amine, such as dimethylaminopropylamine [109-55-7] (7) to give a weak base resia with a tertiary amine fuactioaaHty. [Pg.374]

The cationic acrylamide polymers may contain either tertiary amine or quaternary ammonium groups. Because of their positive charge, they are self-retaining on pulp fibers therefore, they can be used effectively in nonalum systems. [Pg.19]

Cationic Starches. The two general categories of commercial cationic starches are tertiary and quaternary aminoalkyl ethers. Tertiary aminoalkyl ethers are prepared by treating an alkaline starch dispersion with a tertiary amine containing a P-halogenated alkyl, 3-chloto-2-hydtoxyptopyl radical, or a 2,3-epoxypropyl group. Under these reaction conditions, starch ethers are formed that contain tertiary amine free bases. Treatment with acid easily produces the cationic form. Amines used in this reaction include 2-dimethylaminoethyl chloride, 2-diethylaminoethyl chloride, and A/-(2,3-epoxypropyl) diethylamine. Commercial preparation of low DS derivatives employ reaction times of 6—12 h at 40—45°C for complete reaction. The final product is filtered, washed, and dried. [Pg.345]

The majority of U(V1) coordination chemistry has been explored with the trans-ddo s.o uranyl cation, UO " 2- The simplest complexes are ammonia adducts, of importance because of the ease of their synthesis and their versatihty as starting materials for other complexes. In addition to ammonia, many of the ligand types mentioned ia the iatroduction have been complexed with U(V1) and usually have coordination numbers of either 6 or 8. As a result of these coordination environments a majority of the complexes have an octahedral or hexagonal bipyramidal coordination environment. Examples iuclude U02X2L (X = hahde, OR, NO3, RCO2, L = NH3, primary, secondary, and tertiary amines, py n = 2-4), U02(N03)2L (L = en, diamiaobenzene n = 1, 2). The use of thiocyanates has lead to the isolation of typically 6 or 8 coordinate neutral and anionic species, ie, [U02(NCS)J j)/H20 (x = 2-5). [Pg.330]

For vanadium solvent extraction, Hon powder can be added to reduce pentavalent vanadium to quadrivalent and trivalent Hon to divalent at a redox potential of —150 mV. The pH is adjusted to 2 by addition of NH, and an oxyvanadium cation is extracted in four countercurrent stages of mixer—settlers by a diesel oil solution of EHPA. Vanadium is stripped from the organic solvent with a 15 wt % sulfuric acid solution in four countercurrent stages. Addition of NH, steam, and sodium chlorate to the strip Hquor results in the precipitation of vanadium oxides, which are filtered, dried, fused, and flaked (22). Vanadium can also be extracted from oxidized uranium raffinate by solvent extraction with a tertiary amine, and ammonium metavanadate is produced from the soda-ash strip Hquor. Fused and flaked pentoxide is made from the ammonium metavanadate (23). [Pg.392]

Tertiary Amine-Containing Copolymers. Copolymers based on DMAEMA (dimethylarninoethyl methacrylate) in either free amine form or quatemized with diethyl sulfate or methyl chloride have achieved commercial significance as fixatives in hair-styling formulations, especially in the weU-pubhcized "mousses" or as hair-conditioning shampoo additives. This success has occurred because the cationic charge affords substantive resins that strongly adhere to the hair (141). [Pg.533]

It resembles tetracyanoethylene in that it adds reagents such as hydrogen (31), sulfurous acid (31), and tetrahydrofuran (32) to the ends of the conjugated system of carbon atoms suffers displacement of one or two cyano groups by nucleophilic reagents such as amines (33) or sodiomalononittile (34) forms TT-complexes with aromatic compounds (35) and takes an electron from iodide ion, copper, or tertiary amines to form an anion radical (35,36). The anion radical has been isolated as salts of the formula (TCNQ) where is a metal or ammonium cation, and n = 1, 1.5, or 2. Some of these salts have... [Pg.404]

Cation units usually contain a sulphonic acid resin whilst anion resins fall into the two main categories of strongly basic, with quaternary ammonium groupings and weakly basic, with tertiary amine groups. The final unit is the mixed bed in which, by a mixture of cation and anion resins in the same vessel, the effect is achieved of a multiplicity of separate cation and anion units. Resin separation is necessary for regeneration purposes. Considerable improvements in water quality are obtainable by these means. [Pg.834]

Unsymmetrical as well as symmetrical anhydrides are often prepared by the treatment of an acyl halide with a carboxylic acid salt. The compound C0CI2 has been used as a catalyst. If a metallic salt is used, Na , K , or Ag are the most common cations, but more often pyridine or another tertiary amine is added to the free acid and the salt thus formed is treated with the acyl halide. Mixed formic anhydrides are prepared from sodium formate and an aryl halide, by use of a solid-phase copolymer of pyridine-l-oxide. Symmetrical anhydrides can be prepared by reaction of the acyl halide with aqueous NaOH or NaHCOa under phase-transfer conditions, or with sodium bicarbonate with ultrasound. [Pg.490]

Rosenblatt etal have examined the effect of structure and isotopic substitution upon the permanganate oxidation of some alky famines (Table 4). The isotope effect of 1.84 is considered to be sufficiently low to be compatible with aminium radical-cation formation, and it is felt that, while C-H cleavage is significant for oxidation of primary amines, the dominant mode of oxidation of tertiary amines is electron-transfer, e.g. [Pg.319]

Amines are important industrial chemicals which are involved in everyday life [3, 4]. Apart from the usual classification into primary, secondary, and tertiary amines, the distinction is often made between lighf amines (less than six-carbon substituents) and fatty amines. light amines are intermediates for the synthesis of drugs, herbicides, cosmetics, etc. [3]. They also find use as vulcanization accelerators and extraction agents. Fatty amines are involved in the synthesis of corrosion inhibitors and cationic surfactants, which are used in ore flotation processes and are good fabric softeners and antistatic agents [4—6],... [Pg.91]


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See also in sourсe #XX -- [ Pg.534 ]




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Amines tertiary

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