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Aliphatic oxygenates

Solvents. Solvents affect adhesive viscosity, bond strength development, open time, cost, and ultimate strength. Blends of three solvents (aromatic, aliphatic, oxygenates, e.g. ketones, esters) are generally added, and in their selection environmental and safety regulations must be considered. A graphical method has been proposed to predict the most adequate solvent blends for solvent-borne CR... [Pg.664]

The 8-nitro group in intermediate quinolone 225 can be easily displaced even with aliphatic oxygen nucleophiles. Starting compound 224 under various conditions provided directly tricyclic compound 226 and all attempts to isolate the expected intermediate 225 failed (Scheme 34) (91CCC1937). [Pg.214]

An additional example of a cycloamylose-induced rate acceleration which may be reasonably attributed to a conformational effect is the facilitation of the transfer of the trimethylacetyl group from the phenolic oxygen of 9 to the aliphatic oxygen of the adjacent hydroxymethyl group to form 10. This intramolecular transesterification is remarkably enhanced relative to a comparable intermolecular reaction,6 and occurs, at pH 7.0 and 25.5°, with a rate constant of 0.0352 sec-1 (Griffiths and Bender, 1972). An even larger rate enhancement is achieved upon inclusion of this material within the cyclohexaamylose cavity—fc2 = 0.16 sec-1. This fivefold acceleration cannot be satisfactorily explained either by a microsolvent effect which would be expected to depress the rate of the reaction or, at this pH, by covalent... [Pg.248]

As indicated, any given aliphatic chemical is likely to be made by a number of processes from several raw materials. Important examples are acetic anhydride and acetic acid (2) production of the former was about 900,000,000 pounds in 1950 and that of the latter was about half as great. The large demand for these related products is primarily the result of the requirements of cellulose acetate rayon for acetic anhydride. The economic complexities in the production of the aliphatic oxygenated chemicals are probably best illustrated by these two products. [Pg.297]

Barbiturates are absorbed orally and distributed widely throughout the body. They are metabolized in the liver by aliphatic oxygenation, aromatic oxygenation, and A-dealkylation. [Pg.607]

Heterogeneous catalysis has played an important role in the synthesis of aliphatic oxygenated compounds. The present article is devoted specifically to the preparation of ketones and particularly to the work carried out by the authors in the catalysis laboratory of Illinois Institute of Technology. [Pg.207]

In the aliphatic region, subtle differences are observed in the 15-40 ppm range. However, the aliphatic oxygen region of the spectrum (50-95 ppm) exhibits little perceptible difference, being characterized by a broad featureless band in each case. [Pg.44]

Finally, the sensory behaviour of (18) is not as good as that of its smaller ring cousin (14). On the positive side, however, the cation-binding constants remain quantitatively predictable and fluorescence enhancement selectivity peaks at potassium ion. The smaller fluorescence enhancement factor of 3 for (18) with potassium ion can be attributed to lower intrinsic charge density and more charge dispersal to aliphatic oxygen centres than those discussed in the previous paragraph. [Pg.233]

The maximum value of m is derived by assuming that all oxygen-substituted alkyl carbon is in the form of alcohol, all the oxygen-substituted aromatic carbon is hydroxyl, and the carboxylate is in the form of free acid. The minimum value of m is derived by assuming that all carboxylate is linked to aromatic carbon via aromatic esters, the remainder of aromatic oxygen is linked to aliphatic carbon via alkyl aryl ethers, and that the remainder of the aliphatic oxygen linked as aliphatic ethers. [Pg.283]

IV. Anodic Oxidation of Other Aliphatic Oxygen-Containing Compounds... [Pg.589]

IV. ANODIC OXIDATION OF OTHER ALIPHATIC OXYGEN-CONTAINING COMPOUNDS... [Pg.614]

Grosjean, E. and D. Grosjean The Reaction of Unsaturated Aliphatic Oxygenates with Ozone, Journal of Atmospheric Chemistry, 32 (1999) 205-232. [Pg.140]

Barbiturates do not raise the pain threshold and have no analgesic property. In anesthetic doses, they depress aU areas of the CNS, including the hypothalamic thermoregulatory system, respiratory center, and vasomotor centers, as well as the polysynaptic pathways in the spinal column, hi addition, some, such as phenobarbital, but not aU, are anticonvulsants. In toxic doses, barbiturates cause ohguria. They are absorbed orally and distributed widely throughout the body. Barbiturates are metabolized in the fiver by aliphatic oxygenation, aromatic oxygenation, and A-dealkylation. [Pg.67]

The C-NMR spectrum of SAMMl showed 22 carbon resonances none of which was a carbonyl, six of those resonances were in the aliphatic oxygenated region (8 60-80 ppm) (Table 4). One of those six was a quartet (8 60.8 ppm) which indicated the presence of a methoxyl group. The other resonances were characteristic of the sampangine moiety with no substitution at any of its protons. [Pg.35]

Optionally, a second or third transition metal may be added to the ruthenium to further modify its performance and to steer the product distribution toward specific aliphatic oxygenates. These modifiers may be derivatives of rhodium, cobalt, manganese, rhenium, zirconium and titanium, in either halogen-free or halogen-containing forms. [Pg.3]


See other pages where Aliphatic oxygenates is mentioned: [Pg.2172]    [Pg.265]    [Pg.434]    [Pg.300]    [Pg.364]    [Pg.226]    [Pg.771]    [Pg.102]    [Pg.122]    [Pg.296]    [Pg.230]    [Pg.110]    [Pg.44]    [Pg.46]    [Pg.29]    [Pg.233]    [Pg.1928]    [Pg.2422]    [Pg.161]    [Pg.2403]    [Pg.678]    [Pg.115]    [Pg.2176]    [Pg.27]    [Pg.43]    [Pg.156]    [Pg.447]    [Pg.236]    [Pg.110]    [Pg.2]    [Pg.3]    [Pg.13]    [Pg.16]   
See also in sourсe #XX -- [ Pg.110 ]

See also in sourсe #XX -- [ Pg.110 ]




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