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Anionic tertiary amines

Mono P HR5/5 Weak anion Tertiary amine 10 — 2-12 Pharmacia Biotech... [Pg.138]

Several compounds of different classes have been found to be inhibitors and/or activators of serum cholinesterase, and to be useful for distinguishing among some of the cholinesterase variants. These include inorganic anions, tertiary amines, quaternary ammonium compounds, alkyl alcohols, organophosphorus compounds, and carbamates. However, only a few compounds have been extensively used in many laboratories to distinguish variants. [Pg.94]

Hardeners are the second main component of the precursory system, essential to the formation of polyepoxide. They can be a mere cationic (Lewis acid) or anionic (tertiary amine) initiator of chain polymerization. Because oxirane reacts as a bivalent functional group, in this case, the diepoxide precursor is tetravalent and gives spontaneously a highly dense cross-linked network ... [Pg.599]

Bio-Rex 5 2.8 0.70 Intermediate basic anion exchanger with primarily tertiary amines on a polyalkyle-neamine matrix for separation of organic acids. [Pg.1110]

Dowex 4-X4 1.6 0.70 Weakly basic anion exchanger with tertiary amines on an acrylic matrix for the deionization of carbohydrates. Use at pH <7. [Pg.1111]

Many perfluoroaUphatic ethers and tertiary amines have been prepared by electrochemical fluorination (1 6), direct fluorination using elemental fluorine (7—9), or, in a few cases, by fluorination using cobalt trifluoride (10). Examples of lower molecular weight materials are shown in Table 1. In addition to these, there are three commercial classes of perfluoropolyethers prepared by anionic polymerization of hexafluoropropene oxide [428-59-1] (11,12), photooxidation of hexafluoropropene [116-15-4] or tetrafluoroethene [116-14-3] (13,14), or by anionic ring-opening polymeriza tion of tetrafluorooxetane [765-63-9] followed by direct fluorination (15). [Pg.296]

Weak Base. Weak base anion-exchange resins may have primary, secondary, or tertiary amines as the functional group. The tertiary amine -N(CH2)2 is most common. Weak base resins are frequentiy preferred over strong base resins for removal of strong acids in order to take advantage of the greater ease in regeneration. [Pg.372]

Acryhc stroag base anion exchangers (9) are synthesized from acryhc weak base resias. The tertiary amine groups are coaverted to a quaternary ammonium fuactioaahty by reactioa of chloromethane [74-87-3], CH Cl, and the weak base resia. [Pg.375]

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]

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]

Cyanoacrylate adhesives cure by anionic polymerization. This reaction is catalyzed by weak bases (such as water), so the adhesives are generally stabilized by the inclusion of a weak acid in the formulation. While adhesion of cyanoacrylates to bare metals and many polymers is excellent, bonding to polyolefins requires a surface modifying primer. Solutions of chlorinated polyolefin oligomers, fran-sition metal complexes, and organic bases such as tertiary amines can greatly enhance cyanoacrylate adhesion to these surfaces [72]. The solvent is a critical component of these primers, as solvent swelling of the surface facilitates inter-... [Pg.460]

The fluoraza reagents consist of two types of compounds one in which a fluorine atom is bound to the nitrogen atom of an amide or, more often, a sulfonamide and one in which a fluorine atom is bound to the nitrogen atom of a tertiary amine such as pyridine, quinuclidine, or triethylenediamine 1,4-diaza-bicyclo[2 2.2]octane. The positive charge on the nitrogen is counterbalanced by a non-nucleophilic anion such as triflate or tetrafluoroborate. [Pg.150]

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]

The electrophilic character of sulfur dioxide does not only enable addition to reactive nucleophiles, but also to electrons forming sulfur dioxide radical anions which possess the requirements of a captodative" stabilization (equation 83). This electron transfer occurs electrochemically or chemically under Leuckart-Wallach conditions (formic acid/tertiary amine - , by reduction of sulfur dioxide with l-benzyl-1,4-dihydronicotinamide or with Rongalite The radical anion behaves as an efficient nucleophile and affords the generation of sulfones with alkyl halides " and Michael-acceptor olefins (equations 84 and 85). [Pg.216]

The amines require protonation before they can act as anion exchangers and thus show acid extraction properties in the free base form. For example, a tertiary amine has to react with an inorganic acid in accordance with a reaction of the type ... [Pg.513]

Summary New lyophilic cationic silicone surfactants have been synthesized by direct quatemization of halogenated siloxanyl precursors or by transformation of these precursors into tertiary amines with a subsequent quatemization step. After transformation of the precursors into secondary amines, reaction with maleic anhydride and neutralization, new anionic products were obtained. [Pg.267]


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See also in sourсe #XX -- [ Pg.297 ]




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Amine anions

Amines anionic

Amines tertiary

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