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Amines => nitriles

Three generations of latices as characterized by the type of surfactant used in manufacture have been defined (53). The first generation includes latices made with conventional (/) anionic surfactants like fatty acid soaps, alkyl carboxylates, alkyl sulfates, and alkyl sulfonates (54) (2) nonionic surfactants like poly(ethylene oxide) or poly(vinyl alcohol) used to improve freeze—thaw and shear stabiUty and (J) cationic surfactants like amines, nitriles, and other nitrogen bases, rarely used because of incompatibiUty problems. Portiand cement latex modifiers are one example where cationic surfactants are used. Anionic surfactants yield smaller particles than nonionic surfactants (55). Often a combination of anionic surfactants or anionic and nonionic surfactants are used to provide improved stabiUty. The stabilizing abiUty of anionic fatty acid soaps diminishes at lower pH as the soaps revert to their acids. First-generation latices also suffer from the presence of soap on the polymer particles at the end of the polymerization. Steam and vacuum stripping methods are often used to remove the soap and unreacted monomer from the final product (56). [Pg.25]

The most common catalysts in order of decreasing reactivity are haUdes of aluminum, boron, zinc, and kon (76). Alkali metals and thek alcoholates, amines, nitriles, and tetraalkylureas have been used (77—80). The largest commercial processes use a resin—catalyst system (81). Trichlorosilane refluxes in a bed of anion-exchange resin containing tertiary amino or quaternary ammonium groups. Contact time can be used to control disproportionation to dichlorosilane, monochlorosilane, or silane. [Pg.23]

CH3)3Si)2N]2U(CH2Si((CH3)2)N(Si(CH3)3)) Generally, uranium metaUacycles are quite reactive inserting a host of organics, ie, CO, secondary amines, nitriles, isonitriles, aldehydes, ketones, and alcohols. [Pg.335]

Teter et al. filed a series of patents aimed at the production of organic compounds containing nitrogerf or the production of nitriles and amines from ammonia and olefins by passing mixtures of olefin and NH3 over transition metals, mainly cobalt deposited on various supports at 250-370°C and 100-200 bar [27- 3]. With cobalt on asbestos, a mixture of amine, nitrile, olefin hydrogenation product, polymers, and cracking products is obtained (Eq. 4.1) [31]. [Pg.93]

This technique has been applied to the concentration of organochlorine and organophosphorus insecticide [7,8] and various ethers, glycols amines, nitriles, hydrocarbons, and chlorinated hydrocarbons. Although this work was concerned with drinking water, it is a useful technique which may have application in seawater analysis. Cellulose acetate [9], ethyl cellulose acetate [6], and crosslinked polyethyleneinine [8] have been used as semi-permeable membranes. [Pg.364]

Ethers, glycols, amines, nitriles, hydrocarbons, chlorinated Reverse osmosis [522,523]... [Pg.439]

Solvents can be classified into three categories according to their polarity namely, polar protic, dipolar aprotic and non-polar. Most of the common solvents fall under one of following chemical classes Aliphatic hydrocarbons, aromatic hydrocarbons, alcohols, phenols, ethers, aldehydes, ketones, carboxylic acids, esters, halogen-substituted hydrocarbons, amines, nitriles, nitro-derivatives, amides and sulfur-containing solvents (Marcus, 1998). In certain cases a mixture of two or more solvents would perform better than a single solvent. [Pg.116]

Poly glycols (Carbowaxes) Amine, Nitrile, Ether, Ketone, Ester, Alcohol, Aromatics, 100-200... [Pg.437]

In general, the rates of reduction by the ammonium salts are slower than those attained under normal conditions with the lithium salts, but the use of a non-ethereal solvent can be an advantage. Quaternary ammonium aluminium hydrides reduce ketones and amides effectively to alcohols and amines. Nitriles are also reduced to amines, whereas haloalkanes and arenes are reductively dehalogenated to give hydrocarbons in high yield [3]. [Pg.476]

Similar conclusions are also reached for the magnetic shielding of atoms, as revealed by a detailed study of a series of amines, nitriles, ammonia, pyridine, pyra-zine, pyrimidine, and pyridazine [119]. Their local diamagnetic shielding is virtually... [Pg.67]

S. G. Lister, Gen. Synth. Methods 10, 230-319 (1988) Amines, Nitriles, and Other Nitrogen-containing Functional Groups [prepared by General and Synthetic Methods],... [Pg.1336]

C. Ethers, ketones, aldehydes, esters, tertiary amines, nitriles without a-H atoms. [Pg.24]

The cyanato- and, especially, the thiocyanato-boranes form equally stable complexes with amines, nitriles and ethyl acetate (Table 6). The Lewis acidity of these pseudohalogenoboranes and halogenoboranes, with respect to pyridine and ethyl acetate, follows the order Cl >NCS > NCO > F.79... [Pg.88]

Niobium and tantalum halides form adducts with various nitrogen donor ligands including aliphatic and aromatic amines nitriles, Schiffs bases and imidazoles (Table 5). The reactions of MXS with pyridine and related ligands such as bipy or phen depend critically on the reaction conditions. With py at low temperature MX5 (X = Cl, Br) yielded 1 1 adducts that are rapidly reduced to [MX4(py)2] on increasing the temperature, with formation of l-(4-pyridyl)pyridinium halide. Similarly, bipy and phen reduced the metal in MeCN to oxidation state +IV and formed monoadducts of type [MX bipy)] at room temperature, while at 0°C the same reactions yielded [NbCls(bipy)(MeCN)] and [TaX5(bipy)(MeCN)J (X = C1 or Br). NbBrs and Tals formed [MX5(bipy)2], which were formulated as the eight-coordinate [MX4(bipy)2]X.1 Reduction of the metal can however be prevented, even at room temperature,... [Pg.596]

H20, alcohols, amines, nitriles, simple heterocyclics and aromatics... [Pg.16]

Complexes with Amines, Nitriles and Related Ligands 880... [Pg.861]

AMINES. An amine is a derivative of NH3 in which there is a replacement for one or more of the H atoms of Nil, by an alkyl group, such as -CH3 (methyl) or -C2H5 (ethyl) or by an aryl group, such as (>, H (phenyl) or i ll (naphthyl). Mixed amines contain at least one alkyl and one aryl group as exemplified by methylphenylamine CH3 Nnij O.H . When one, two, and three H atoms arc thus replaced, the resulting amines ate known as primary, secondary, and tertiary, icspectively. Thus, methylamine, CH3NH2, is a primary amine dimethylamine, iCHj) NH, is a secondary amine and trimethylamine. (CHs N. is a tertiary amine. Secondary amines sometimes are called imines tertiary amines, nitriles. [Pg.74]

SCHMIDT REACTION. Acid catalyzed addition of hydrazonic acid to carboxylic acids, aldehydes, and ketones to give amines, nitriles, and amides, respectively. [Pg.1462]

Amines are at the same low oxidation level as alcohols and consequently are easily prepared by reduction. Amides and nitriles are reduced efficiently by LAH to amines. Nitriles give only primary amines while amides give 1°, 2°, or 3° amines depending on the number of carbon substituents on the amide nitrogen. The advantage of this method is that amides are easy to prepare from acid chlorides and amines while nitriles are available by displacement reactions. [Pg.202]

Complexants other than alcohols (e.g., amines, nitriles, tert-butyl compounds, surfactants, and multiple fluorophores) can also be detected by the method of Scheme 2 [279-284], Bohne and Yang have replaced alcohols with amino acids [285], although the zwitterionic charge distribution and increased steric requirements of the former lead to smaller stability constants of the ternary complex. Notwithstanding, tryptophan, leucine, and phenylalanine produce measurable changes in the I III ratio of pyrene emission, thereby allowing for their detection at mM levels. [Pg.28]

The acid-catalysed reaction of hydrogen azide with electrophiles, such as carbonyl compounds, tertiary alcohols or alkenes. After a rearrangement and extrusion of N2, amines, nitriles, amides or imines are produced. [Pg.207]

Although, at that time, the term supramolecular chemistry had not yet been coined, the practical potential for inclusion complexation for acetylene alcohol guests 1 and 2 was recognized back in 1968 [12], Spectroscopic studies showed that 1 and 2 formed molecular complexes with numerous hydrogen-bond donors and acceptors, i.e. ketones, aldehydes, esters, ethers, amides, amines nitriles, sulfoxides and sulfides. Additionally, 1 formed 1 1 complexes with several n-donors, such as derivatives of cyclohexene, phenylacetylene, benzene, toluene, etc. The complexation process investigated by IR spectrometry revealed the presence of OH absorption bands at lower frequencies than those for uncomplexed 1 and 2 [12], These data, followed by X-ray studies, confirmed that the formation of intermolecular hydrogen bonds is the driving force for the creation of complexes [13],... [Pg.5]

Begin to recognize the important functional groups alkene, alkyne, alcohol, ether, aldehyde, ketone, carboxylic acid, ester, amine, nitrile, amide, thiol, and thioether. [Pg.3]

Straight Chain Compounds Q to about Cio and more in many cases Alcohols, alkyl halides, acids, aldehydes, amines, nitriles, ketones. [Pg.80]

Urea forms an isomorphous series of crystalline non-stoichiometric inclusion compounds with n-alkanes and their derivatives (including alcohols, esters, ethers, aldehydes, ketones, carboxylic acids, amines, nitriles, thioalcohols, and thioethers), provided that their main chain contains six or more carbon atoms. [Pg.350]


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