Chemistry conjugated

The functional groups used for click chemistry conjugations are completely unreactive toward biological molecules and virtually free of side reactions, which otherwise would cause reagent... 

M. Schott, in Nobel Symposium in Chemistry Conjugated Polymers and Related Materials The Interconnection of Chemical and Electronic Structure, W. R. Salaneck, I. Lundstrom and B. Rlnby (Eds) (Oxford Scientific, Oxford, 1993), p. 377. 

In their qualitative chemistry, conjugated dienes behave very much like alkenes They readily react with electrophiles in addition reactions. Just as in the case of alkenes. this addition proceeds to give the most stable intermediate. For conjugated dienes, this normally turns out to be a re.sonance stabilized allylic cation ... 

Alkylation of 2-methylaminothiazole (204) with ROH in 85% sulfuric acid gives 2-methylimino-3-alkyl-4-thiazoIine (54). 2-Amino-4-rnethyl-thiazoie alkylated with an excess of isopropanol, however, gives 95% of 2-isopropylamino-4-methyl-5-isopropylthiazole (56). The same result is obtained with cyclohexanol (242). These results and those reported in Sections III.l.C and IV.l.E offer interesting new synthetic possibilities in thiazole chemistry. The reactive species in these alkylations is the conjugate acid of 2-aminothiazole. and the diversity of the products obtained suggests that three nucleophilic centers may be operative in this species. 

A particular kind of conjugate addition reaction earned the Nobel Prize in chemistry for Otto Diels and Kurt Alder of the University of Kiel (Germany) m 1950 The Diels-Alder reaction is the conjugate addition of an alkene to a diene Using 1 3 buta diene as a typical diene the Diels-Alder reaction may be represented by the general equation... 

Carey Organic Chemistry I 10 Conjugation in Fifth Edition Alkadienes and Allylic... 

In most biochemical reactions the pH of the medium is close to 7 At this pH car boxylic acids are nearly completely converted to their conjugate bases Thus it is common practice m biological chemistry to specify the derived carboxylate anion rather than the carboxylic acid itself For example we say that glycolysis leads to lactate by way of pyruvate... 

The General References and two other reviews (17,25) provide extensive descriptions of the chemistry of maleic anhydride and its derivatives. The broad industrial appHcations for this chemistry derive from the reactivity of the double bond in conjugation with the two carbonyl oxygens. 

The quiaones have excellent redox properties and are thus important oxidants ia laboratory and biological synthons. The presence of an extensive array of conjugated systems, especially the a,P-unsaturated ketone arrangement, allows the quiaones to participate ia a variety of reactioas. Characteristics of quiaoae reactioas iaclude nucleophilic substitutioa electrophilic, radical, and cycloaddition reactions photochemistry and normal and unusual carbonyl chemistry. 

In aqueous solution, closo borane anions are very stable as their conjugate acids, which possess acidity similar to sulfuric acid, yet their chemistry is remarkably different. Large unipositive cations, such as Tl", Cs", Rb", [(CH2)4N]", and [(CH2)3S]", yield water-iasoluble salts of ... 

The monomer, CPD, obtained via cracking of the dimer, DCPD, and the dimer both have extensive uses. Cyclopentadiene is probably the most widely studied conjugated, cycHc diolefin system. Eleven review articles dealing with the chemistry of cyclopentadiene have been pubHshed (1—11). An article dealing specifically with European uses of DCPD has also been pubHshed (12). The discovery ia 1951 of stable metal derivatives has given additional impetus to the study of the chemistry of cyclopentadiene. Eive review articles have been pubHshed on this subject (13—17). 

Conjugated Systems and Their Physicochemical Properties, in Advances in Quantum Chemistry. Vol. 17, ed. P. -O. Lbwdin, Academic Press, New York, 1985, pp. 251 and references therein. 

Our discussion of chemical reactions of alkadienes will be limited to those of conjugated dienes. The reactions of isolated dienes are essentially the same as those of individual alkenes. The reactions of cumulated dienes are—like their preparation— so specialized that their treatment is better suited to an advanced course in organic chemistry. 

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