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G Amines

The first two are very soluble in water but the last is less so. Weaker bases inelude ammonium hydroxide where X is NH4. In faet every aeid ean generate a base by loss of a proton and the definition now ineludes any eompound eapable of donating eleetron pairs, e.g. amines. Bases turn litmus paper blue and show eharaeteristie effeets on other indieators. They are soluble in water, tarnish in air, and in eoneentrated form are eorrosive to the toueh. Common examples are given in Table 3.5. ... [Pg.28]

Epichlorohydrin with bisphenol A. The curing agents may pose significant health hazards, e.g. amines (triethylamine, p-phenylenediamine, diethylenetriamine) or acid anhydrides (pyromellitic dianhydride)... [Pg.144]

Ion exchange, in which cation and/or anion resins are used to replace undesirable anionic species in liquid solutions with nonhazardous ions. For example, cation-exchange resins may contain nonhazardous, mobile, positive ions (e g., sodium, hydrogen) which are attached to immobile acid groups (e.g., sulfonic or carboxylic). Similarly, anion-exchange resins may include nonhazardous, mobile, negative ions (e.g., hydroxyl or chloride) attached to immobile basic ions (e.g., amine). These resins can be used to eliminate various species from wastewater, such as dissolved metals, sulfides, cyanides, amines, phenols, and halides. [Pg.17]

For resistance to acid conditions alone, traditional filled and unfilled bituminous solutions (which have economic advantages), chlorinated rubber and shellac have been used. Crosslinking coatings, e.g. amine-cured epoxy resins, often blended with coal-tar which develops resistance to oils and solvents, have obvious advantages on chemical plant. [Pg.612]

KOH is the most frequently used base, though stronger bases (OR , NH, etc.) or weaker ones (e.g., amines) are used where warranted.The bicyclic amidines l,5-diazabicyclo[3.4.0]non-5-ene (DBN) and are good reagents... [Pg.1337]

The ZwKKER reaction involving Co salts is frequently used for the detection of barbituric acid derivatives [31-35], but some purine, pyridine and piperidine derivatives and heterocyclic sulfonamides also yield colored derivatives. The Zwkker reaction is particularly sensitive when it is possible to form a tetrahedral complex [Co(Barb)2 Xj] (X = donor ligand, e.g. amine) [4]. [Pg.67]

Ligand A anionic (e.g., halides, pseudohalides, alkyl, aryl, thiolate, alkoxide) ligand N neutral (e.g., amines, imines, phosphines, carbenes, nitriles, isonitriles, NO, CO) ligand C cationic (e.g., NO+)... [Pg.180]

Dorow, R, Horowski, R, Paschelke, G, Amin, M and Braestrup, C (1983) Severe anxiety induced by FG7142, a /i-carboline ligand for benzodiazepine receptors. Lancet ii 98-99. [Pg.421]

The syntheses described in the preceding section can be performed using as stabilizers the classical ligands of organometalhc chemistry (e.g., amines, thiols, or phosphines) instead of polymers. The amount of ligand added allows control of the particle growth and therefore the size. [Pg.243]

More than 200 users annually consume over US 55 million of light stabilisers. IR absorbers (e.g. amine, antimony salt mixture) protect against IR radiation applicable in PC, PMMA, PVC, etc. [Pg.781]

It should be noted that liquefaction at times occurs because of eutectic formation (e.g., often with caffeine combinations) and that this may not necessarily be associated with decomposition. On the other hand, discoloration (e.g., amines and sugars) usually is. [Pg.186]

As base B several electron donors can be employed, e.g. amines 127), hydrazines128), amine oxides129, ethers126, phosphanes 130>131, and even charged ligands such as halogen anions 126) and many others 126). There may be formed either 1 1 or 1 2 adducts as in Eq. (7), an equilibrium being assumed to be established between these two adducts ... [Pg.33]

In addition to these three groups, there are some other examples, e.g., amines [108-110], phenols [111-113], metal ions [114-117], oxalic acid [118,... [Pg.145]

Watanabe reports a new method for the direct conversion of o-choroacetaldehyde N,N-disubstituted hydrazones into 1-aminoindole derivatives 93 by palladium-catalyzed intramolecular ring closure of 92 in the presence of P Bu3 or the bisferrocenyl ligand 94 <00AG(E)2501>. When X = Cl, this cyclizative process can be coupled with other Pd-catalyzed processes with nucleophilic reagents (e.g., amines, azoles, aryl boronic acids) so as to furnish indole derivatives with substituents on the carbocyclic ring. [Pg.118]

In most cases, metal ion coordination by a dendrimer takes place by units that are present along the dendrimer branches (e.g., amine, imine, or amide groups) or appended at the dendrimer periphery (e.g., terpyridine, cathecolamide ligands). When multiple identical coordinating units are present, dendrimers give rise to metal complexes of variable stoichiometry and unknown structures. Luminescent dendrimers with a well defined metal-coordinating site have been reported so far [16, 17], and the most used coordination site is 1,4,8,11-tetraazacyclotetradecane (cyclam). [Pg.255]

For neutral nucleophiles (e.g. amines, alcohols, water) there is much evidence that the addition-elimination mechanism depicted in equation 1 fits very well most of the intermolecular and intramolecular nucleophilic displacements involving nitro-activated aromatic substrates1. [Pg.1216]


See other pages where G Amines is mentioned: [Pg.193]    [Pg.283]    [Pg.63]    [Pg.304]    [Pg.818]    [Pg.299]    [Pg.812]    [Pg.203]    [Pg.459]    [Pg.13]    [Pg.162]    [Pg.403]    [Pg.454]    [Pg.310]    [Pg.374]    [Pg.664]    [Pg.583]    [Pg.117]    [Pg.163]    [Pg.187]    [Pg.43]    [Pg.422]    [Pg.1077]    [Pg.514]    [Pg.294]    [Pg.19]    [Pg.54]    [Pg.230]    [Pg.128]    [Pg.541]    [Pg.113]    [Pg.670]   


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Reaction G Aldehyde-Amine Condensation

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