Elimination, pages

Belyaev, Yu. A. (1969). "i41Am distribution in rats and the effect of complexing substances on its elimination, page 168 in Radioactive Isotopes and the Body, Report No. AEC-tr-7195, Moskalev, Yu.I., Ed. (National Technical Information Service, Springfield, Virginia). 

Similarly, heating 2-butanol in the gas phase with a catal)dic amoimt of HBr at temperatures of 387-510°C was foimd to produce a mixture of water, 1-butene, a s-2-butene, and frflns-2-butene. The reaction was overall second order, first order in alcohol and first order in HBr. The reaction was imaffected by additives expected to retard the rates of radical reactions, so a molecular reaction pathway seemed most likely. Several bimolecular mechanisms were considered, but a mechanism involving the transition structure shown in equation 10.66 is particularly interesting because of the resemblance of this transition structure to those proposed for pyrol)rtic eliminations (page 681). ... 

There is a small trick at this point, which eliminates pages of discussion. Barrow [4] shows this method and expands it over three chapters. We form the ratio of the population in one given quantum level, to the total number of molecules in the sample to obtain a useful formula. 

A -Oleflns in the 5a-series are frequently formed by elimination from the tosylates of 3j5-alcohols. Contamination with A -compound is common, and puriflcation via a derivative (e.g. dibromide) may be necessary (see page 343). A 2-methyl substituent increases the selectivity ... 

When comparing calculated results to thermodynamic quantities extrapolated to zero Kelvin, the zero point energy needs to be added to the total energy. As with the frequencies themselves, this predicted quantity is scaled to eliminate known systematic errors in frequency calculations. Accordingly, if you have not specified a scale factor via input to the Reodlsotopes option, you will need to multiply the values in the output by the appropriate scale factor (see page 64). 

These reactions can take place by either heterolytic or pericyclic mechanisms. Examples of the latter are shown on page 1322. Free-radical P eliminations are extremely rare. In heterolytic ehminations, W and X may or may not leave simultaneously and may or may not combine. 

Smith, M.B. Hrubiec, R.T. Tetrahedron, 1984, 40, 1457 Hrubiec, R.T. Smith, M.B. J. Org. Chem., 1984,49, 385 Hrubiec, R.T. Smith, M.B. Tetrahedron Lett., 1983,24, 5031. This mechanism has also been called the addition-elimination mechanism, but in this book we limit this term to the type of mechanism shown on page 428. 

Effect of Solvent on Elimination versus Substitution. Increasing polarity of solvent favors Sn2 reactions at the expense of E2. In the classical example, alcoholic KOH is used to effect elimination, while the more polar aqueous KOH is used for substitution. Charge-dispersal discussions, similar to those on page 450, only partially explain this. In most solvents, SnI reactions are favored over El. The El reactions compete best in polar solvents that are poor nucleophiles, especially dipolar aprotic solvents" A study made in the gas phase, where there is no solvent, has shown that when 1-bromopropane reacts with MeO only elimination takes place no substitution even with this primary substrate." ... 

Because of the mildness of the procedure, this is probably the best means of accomplishing this conversion. See page 555 for another application of the selenoxide reaction. Allylic sulfoxides undergo 1,4 elimination to give dienes. 

S. Talabani and G. Hareland. New cement additives that eliminate cement body permeability. In Proceedings Volume, pages 169-176. SPE Asia Pacific Oil Gas Conf (Kuala Lumpur, Malaysia, 3/20-3/22), 1995. 

Irradiation of a mixture of androstane (28) and cholestane (29) followed by oxidation of the product oximes to nitriles and mass spectrometric analysis revealed a N15/N14 ratio of 1 1.32 for the product derived from (28) and a N16/N14 ratio of 1 1.25 for the product derived from (29). Thus mechanism (a) is effectively eliminated, see top of facing page. 

Compounds not eliminated by the counterscreen are re-tested in a secondary assay involving in vitro translation of FF/HCV/Ren mRNA in Krebs-2 extracts using 35S-methionine followed by SDS-PAGE analysis to monitor protein synthesis... 

Q. You will note that the first paragraph talks about buna as a vital war material. On page 13 Dr. ter Meer, you stated that the war "started a bit too early as lar as supplying Germany s rubber requirements from home production was concerned. Fortunately, it was possible to eliminate them by seizing considerable stocks of natural rubber in the enemy countries and by import via Japan and Russia." Then you state "Production today nearly covers present requirements." Is this an accurate statement of the situation ... 

Miller, D.L., J.P. Corliss, R.N. Farragut, and H.C. Thompson, Jr. 1982. Some aspects of the uptake and elimination of the polynuclear aromatic hydrocarbon chrysene by mangrove snapper, Lutjanus griseus, and pink shrimp, Penaeus duorarum. Pages 321-335 in N.L. Richards and B.L. Jackson (eds.). Symposium Carcinogenic Polynuclear Aromatic Hydrocarbons in the Marine Environment. U.S. Environ. Protection Agency Rep. 600/9-82-013. 

Instrumental correction for background absorption using a double beam instrument or a continuum source has already been discussed (p. 325). An alternative is to assess the background absorption on a non-resonance line two or three band-passes away from the analytical line and to correct the sample absorption accordingly. This method assumes the molecular absorption to be constant over several band passes. The elimination of spectral interference from the emission of radiation by the heated sample and matrix has been discussed on page 324 et seq. 

Retroaldolisation of (+)pulegone (32) afforded (/ )-3-methylcyclohexanone 33 (see Chapter 3, page 72), which was dehydrogenated through the well known sulphoxide elimination process [13] furnishing optically pure 31 in 49% overall yield (Scheme 13.2.10). 

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