And ester formation

Hypochlorous acid undergoes a variety of reactions with organic substances including addition, oxidation, C- and iV-chlorination, and ester formation. On an industrial scale, hypochlorous acid, generated m situ via chlorine hydrolysis, reacts with propylene forming primarily the a-propjlene chlorohydrin isomer. 

In an attempt to use an acyl anion equivalent to open an aziridine, Wu and co-workers isolated an unexpected ring opened product 316 (Eq. 31) [158], The authors found that the presence of oxygen was the determining factor between benzoin formation and ester formation. No desired ketones were ever formed. Various aromatic substituted aldehydes were treated under standard reaction conditions to afford esters in good yields. 4-Methoxybenzaldehyde provided product in only 40% yield, presumably due to the ease of aldehyde oxidation. 

Reactions of A-acyloxy-A-alkoxyamides (90) with A-methylaniline in methanol or aqueous acetonitrile afforded quantitative yields of esters (130), carboxylic acid (132) and half an equivalent of A,A -dimethyl-A,A -diphenyltetrazene (131) (equation 15). The reaction is promoted by polar solvents and ester formation was shown to involve an intramolecular process a crossover experiment using a mixture of A-acetoxy-iV-butoxy-4-toluamide (90, R = Bu, R = Me, R = 4-MeC6H4) and A-acetoxy-A-ethoxybenzamide (90, R = Et, R = Me, R = Ph) afforded clean yields of butyl 4-toluate (130, R = Bu, R = 4-McC6H4) and ethyl benzoate (130, R = Et, R = Ph)". ... 

These reactions are in equilibrium at any time. When the carbonylation reaction s rate is low, side reactions, e.g. ether and ester formation, can predominate. On the other hand a high carbonylation rate results in removing the available methanol from the reaction mixture and sub-... 

This mechanism has been suggested by Lane38 as the best rationalization of the available evidence. It has the merit that the second water molecule plays a simple, integral part in the transition state, and is consistent with as many of the observed facts as is any other mechanism. In particular it is a symmetrical mechanism, applicable equally to acid-catalyzed hydrolysis and ester formation. It does, however, involve a termolecular collision, and this fact is at variance with the observed entropy of activation, as discussed above. 

The relative rate of amide and ester formation depends on the nature of the zeolite but we observe generally a rapid stabilization of the amide concentration while the ester concentration shows a linear dependence against tii.ie. A typical example is described for a HM (Si/A1 =8) (Fig. 3). The signi-... 

Retinoic acid is insoluble in water but soluble in many organic solvents. It is susceptible to oxidation and ester formation, particularly when exposed to light. Topically applied retinoic acid remains chiefly in the epidermis, with less than 10% absorption into the circulation. The small quantities of retinoic acid absorbed following topical application are metabolized by the liver and excreted in bile and urine. 

Oxidation of Monosaccharides Reducing Sugars 1117 23-11 Nonreducing Sugars Formation of Glycosides 1119 23-12 Ether and Ester Formation 1121... 

Chemical Properties.—The chemical reactions of phosphoric acid can be classified mainly under salt and ester formation, hydration, dehydration (see p. 170) and complex formation. Towards reducing and oxidising agents the aqueous solution is comparatively inert. 

In general the role of the anions derived from Br nsted acids should be viewed in terms of their nucleophilicity, e.g. the facility with which they can recombine vritii the carbocation. Anions like Cl and CHsCOO have a pronounced tendency to form covalent bonds with carbon and therefore, except under very special circumstances such as extremely basic monomers or very polar media, the lifetime of ionic chain carriers will be very limited with such counterions. As we diall see, this situation is in fact much more general than commonly believed, and ester formation is quite important with practically all Br nsted acids. 

Considering that the chemical reactivity of carboxylic acids is similar to that of carbonic acids, as is observed in amide and ester formation, we have attempted the substitution of carbon dioxide for carboxylic acids in the coupling reaction with amines by using phosphites in pyridine or imidazole, and found that ureas are in fact produced in good yields (Eq. (4))6. Similarly, carbon disulfide reacts with amines to yield the corresponding thioureas (Eq. (5)). 

Alcohol Acetyl Transferase Genes and Ester Formation in Brewer s Yeast... 

Alcohol acetyl transferase genes and ester formation in brewer s yeast—Continued ATFl gene regulation and promoter replacement, 203-205/ cloning of ATFJ genes, 197-199,204 experimental description, 197 Aldehydes, long-chain fatty, biogeneration via oxylipins in edible seaweeds, 146-164... 

Halogenation and nitration of arenes, substitution reactions ofaliphatics Ether and ester formation, thiols from alcohols and H2S, amines from alcohols and NHj (mordenite, erionite)... 

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