Reactivity for organic compounds

Intermolecular Electron Transfer Reactivity for Organic Compounds Studied Using Marcus Cross-Rate Theory... 

INTERMOLECULAR ELECTRON TRANSFER REACTIVITY FOR ORGANIC COMPOUNDS... 

Siskin M, Katritzky AR (1991) Reactivity of organic compounds in hot water geochemical and technological implications. Science 254 231-237 Schubert K, Brandner J, Fichtner M, Linder G, Schygulla U, Wenka A (2001) Micro structure devices for applications in thermal and chemical process engineering. Microscale Thermophys Eng 5 17-39 Thayer AM (2005) Harnessing microreactions. Chem Eng News Coverstory 83 43-52. 

The introduction of a substituent in an organic compound may affect its reactivity in a given reaction. A number of quantitative relationships have been suggested in connection with the effect of substituents on the rate constant of the reaction. Such structure-reactivity co-relations are helpful in predicting the reactivity of organic compounds in various reactions and also in verifying the reaction mechanism. One such useful relationship was proposed by Hemmett, which relates the equilibrium and rate constants for the reaction of meta and para substituted benzene derivatives. 

Uses. Reactive diluent for epoxy resins stabilizer for organic compounds chemical intermediate for synthesis of ethers and esters... 

As the first commercial NMR instruments became available, a significant part of the empirical knowledge related to the structure and reactivity of organic compounds was under close scrutiny. Model compounds that could be used to test certain concepts or effects were subject to spectroscopic techniques and a framework for interpreting spectra based on structural properties began to develop. 

The substitution method and the interconversion reactions discussed for proof of structure possibly may give you erroneous ideas about the reactions and reactivity of organic compounds. We certainly do not wish to imply that it is a simple, straightforward process to make all of the possible substitution products of a compound such as... 

It is well documented that the structure of organic pollutants and speciation of inorganic pollutants determine the effectiveness of treatment by different technologies. For example, AOPs are used to destroy organic pollutants based on the molecular structures of the pollutants. In terms of reactivity of organic compounds, the following order may be expected ... 

Some preliminary examples of hydrolysis reactions illustrate the very wide range of reactivity of organic compounds. For example, triesters of phosphoric acid hydrolyze in nearneutral solution at ambient temperatures with half-lives ranging from several days to several years (Wolfe, 1980), whereas the halogenated alkanes pentachloroethane, carbon tetrachloride, and hexachloroethane have "environmental" (pH = 7 25°C) half-lives of about 2 hr, 50 yr, and 1000 millennia, respectively (Mabey and Mill, 1978 Jeffers et al., 1989). On the other hand, pure hydrocarbons from methane through the PAHs are not hydrolyzed under any circumstances that are environmentally relevant. 

Reactivity of organic compounds toward HO is estimated readily in most cases because of the large databases of values measured for reactions in water and air and the correlation equations relating rates of oxidation of aliphatic compounds in air and water, as well as the availability of Hammett SARs for reactions of aromatic compounds. In addition, 90% of HO rate constants in water and air are within 50% of 5 x 109 M 1 s Thus, the limiting indirect photoreaction rate constant for almost any compound in freshwater with more than 1 mg/L of NO3 will be 1.5 x 10 7 s 1 at 40°-50° latitude in summer, equivalent to a 50-day half life. In low-nitrate waters, the limiting half life will be extended correspondingly. 

Ground-state stabilization by hyperconjugation can modify the reactivity of organic compounds significantly, and must be taken into account when estimating the stability of certain types of compound. Di- or polysubstituted methanes can have high ground-state stability if the substituents are simultaneously a-acceptors and jt-donors, as is observed for many heteroatoms. If, on the other hand, the substitu-... 

R. W. Taft (1922-1996) was professor of chemistry at Pennsylvania State College and then for thirty years at the University of California, Irvine. He did distinguished work in several fields of physical organic chemistry, e.g. structure-reactivity relationships, gas-phase reactivity of organic compounds, and the correlation analysis of solvent effects.299,300... 

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