Hydrolysis aminolysis

Surfactants have also been of interest for their ability to support reactions in normally inhospitable environments. Reactions such as hydrolysis, aminolysis, solvolysis, and, in inorganic chemistry, of aquation of complex ions, may be retarded, accelerated, or differently sensitive to catalysts relative to the behavior in ordinary solutions (see Refs. 205 and 206 for reviews). The acid-base chemistry in micellar solutions has been investigated by Drummond and co-workers [207]. A useful model has been the pseudophase model [206-209] in which reactants are either in solution or solubilized in micelles and partition between the two as though two distinct phases were involved. In inverse micelles in nonpolar media, water is concentrated in the micellar core and reactions in the micelle may be greatly accelerated [206, 210]. The confining environment of a solubilized reactant may lead to stereochemical consequences as in photodimerization reactions in micelles [211] or vesicles [212] or in the generation of radical pairs [213]. 

The enhanced acidity of the thiadiazole acids is reflected in the reactivity of the corresponding esters which undergo hydrolysis, aminolysis, and hydrazinolysis with extreme ease. Thia-diazoleamides and -hydrazides behave normally in the Hofmann and Curtius reactions. 

Catalysis arising solely from hydrophobic interactions between the reactants in model systems has been investigated recently by Knowles and Parsons (1967, 1969). The effects of hydrophobic interactions on the rate of hydrolysis, aminolysis, and imidazole-catalyzed hydrolysis of p-nitrophenyl esters were elucidated by varying the hydrocarbon chain length of the -nitrophenyl ester, the primary amine, and the N-substituted imidazole and determining the second order rate constants at concentrations well below the CMCs of the reactants, conditions under which cationic (amine) and neutral (ester) micellar catalysis is... 

Oxidation and reduction procedures have little effect on 1-aryl substituents which are also very difficult to remove. When, however, there are strongly electron-withdrawing groups present in the benzene ring, nucleophiles are effective in promoting dearylation. Thus, a 2,4-dinitrophenyl group at N-1 of histidine is cleaved by alkaline hydrolysis, aminolysis or hydrazinolysis. On the other hand, l-(2-pyridyl)imidazole is cleaved neither by 2M sodium hydroxide nor by 2M hydrochloric acid. 

A fairly extensive metathetical chemistry of diboron compounds has been developed which provides the means for synthesis of specific derivatives from more commonly available starting materials such as tetrachloro-diborane(4) and the tetrakis(dialkylamino)diboron derivatives. Thus, reactions involving hydrolysis, aminolysis, alcoholysis, transamination, etc., are available for interconversions of diboron compounds by pathways analogous to those known in monoboron chemistry. Examples of such reactions include the following ... 

General base-catalyzed alkaline amide hydrolysis, aminolysis of carboxylate ion. 

Many carboxy derivatives are available by primary syntheses. Otherwise the best route to simple pyrimidinecarboxylic acid derivatives is oxidative. This statement is even more applicable to our present situation with readily available acyl-, alkenyl-, or alkynylpyrimidine substrates from the coupling procedures, which serve as excellent substrates for oxidative reactions. The normal carboxylic acid reactions are observed ester formation, ester hydrolysis, aminolysis, acid chloride formation and reactions. A carboxy group in an electrophilic position may readily be lost when the pyrimidine ring is further depleted of 7t-electrons by its substitution pattern selective decarboxylation can be effected in pyrimidinedicarboxylic acids. 

Detailed kinetic stndies on the rates of hydrolysis " , aminolysis", and thiolysis" " of 9-aminoacridine and its A-substituted derivatives revealed that the rate of thiolysis is mnch faster than those of aminolysis and hydrolysis under similar experimental conditions. This difference in the reactivity of thiols and amines as well as HO/H2O toward 9-aminoacridine and its N-substituted derivatives is ascribed partly to the fact that HO/H2O, RO/ROH, and amines are hard, whereas thiols are soft nncleophiles," and as the reactive centers in 9-aminoacridine and its Af-substituted derivatives are soft electrophilic in nature, a soft nucleophile should react much faster than a hard nucleophile of comparable basicity. 

It is generally accepted that transamidation is not a concerted reaction, but occurs through the attack of a free end on the amide group via aminolysis (eg, eq. 4) or acidolysis (eg, eq. 3) (65). Besides those ends always present, new ends are formed by degradation processes, especially hydrolysis (eq. 5), through which the amide groups are in dynamic equiUbrium with the acid and amine ends. 

Chemistry. Poly(vinyl acetate) can be converted to poly(vinyl alcohol) by transesterification, hydrolysis, or aminolysis. Industrially, the most important reaction is that of transesterification, where a small amount of acid or base is added in catalytic amounts to promote the ester exchange. 

Pyrimidine, 5-acetyI-2,4-dimethyI-synthesis, 3, 125 Pyrimidine, acylamino-deaeylation, 3, 85 Pyrimidine, alkoxy-hydrolysis, 3, 91 Primary Synthesis, 3, 134 synthesis, 3, 132, 134 Pyrimidine, 2-alkoxy-aminolysis, 3, 92 rearrangement, 3, 92, 135 synthesis, 3, 134 transalkoxylation, 3, 92 Pyrimidine, 4-alkoxy-aminolysis, 3, 92 rearrangement, 3, 92, 135 synthesis, 3, 134 transalkoxylation, 3, 92 Pyrimidine, 6-alkoxy-aminolysis, 3, 92 rearrangement, 3, 92, 135 synthesis, 3, 134 transalkoxylation, 3, 92 Pyrimidine, alkyl-halogenation, 3, 76 nitration, 3, 77 oxidation, 3, 76 synthesis, 3, 124... 

Pyrimidine, I-alkyl-2-methyltetrahydro-C-thioacylation, 4, 807 Pyrimidine, 4-alkylsulfinyl-nucleophilie displaeement reaetions, 3, 97 Pyrimidine, 6-alkylsulfinyl-nucleophilic displacement reactions, 3, 97 Pyrimidine, 2-alkylsulfonyl-nueleophilie displaeement reactions, 3, 97 Pyrimidine, 4-alkylsulfonyl-nucleophilic displacement reactions, 3, 97 Pyrimidine, 6-alkylsulfonyl-nucleophilie displaeement reactions, 3, 97 Pyrimidine, alkylthio-dealkylation, 3, 95 desulfurization, 3, 95 oxidation, 3, 96 synthesis, 3, 135, 136 Pyrimidine, 2-alkylthio-aminolysis, 3, 96 hydrolysis, 3, 95 Prineipal Synthesis, 3, 136 Pyrimidine, 4-alkylthio-aminolysis, 3, 96 hydrolysis, 3, 95 Pyrimidine, 6-alkylthio-aminolysis, 3, 96 hydrolysis, 3, 95 Pyrimidine, 4-allenyloxy-rearrangement, 3, 93 Pyrimidine, 4-allyloxy-2-phenyl-rearrangement, 3, 93 Pyrimidine, 4-allynyloxy-rearrangement, 3, 93 Pyrimidine, 4-anilino-2,5,6-trifluoro-NMR, 3, 63 Pyrimidine, 2-aryl-pyrroleaeetic aeid from, 4, 152 Pyrimidine, arylazo-synthesis, 3, 131 Pyrimidine, 4-arylazo-reduetion, 3, 88... 

Pyrimidine, 4-efaloro-2-metfayltfaio-thiolysis, 3, 102 Pyrimidine, 5-cyano-synthesis, 3, 129 Pyrimidine, 4,6-dibenzyloxy-hydrolysis, 3, 91 Pyrimidine, diefaloro-aminolysis, 3, 99 Pyrimidine, 2,4-diefaloro-aminolysis, 3, 99 Pyrimidine, 4,6-diefaloro-aleofaolysis, 3, 100 aminolysis, 3, 99... 

Pyrimidine, 4-fluoro-2-isopropyl-synthesis, 3, 140 Pyrimidine, 4-fluoro-2-methoxy-synthesis, 3, 140 Pyrimidine, 4-fluoro-2-methyl-NMR, 3, 63 Pyrimidine, halo-aleoholysis, 3, 100 aminolysis, 3, 99 as antitumour agents, 3, 152 bipyrimidines from, 3, 103 Buseh biaryl synthesis, 3, 103 hydrolysis, 3, 101... 

Pyrimidine-5-carbonitrile, 4-amino-6-methyl-synthesis, 3, 114 Pyrimidinecarbonitriles alcoholysis, 3, 83 aminolysis, 3, 83 hydrolysis, 3, 83, 127 oxides... 

Pyrimidine-4(3H)-thione, 6-methoxy-5-nitro-reduction, 3, 88 Pyrimidinethiones acidic pK, 3, 60 S-acylation, 3, 95 N-alkylated synthesis, 3, 139 aminolysis, 3, 94 desulfurization, 3, 93 electrophilic reactions, 3, 69 hydrolysis, 3, 94 oxidation, 3, 94, 138 pyrimidinone synthesis from, 3, 133 reactions... 

In this series of amides, hydrolysis or aminolysis of a simple ester, cleavage of a silyl groups a cis/trans isomerization, or reduction of a quinone to a hydro-quinone exposes an alcohol that then induces deprotection by intramolecular addition to the amide carbonyl. 

Modification of the Erlenmeyer reaction has been developed using imines of the carbonyl compounds, obtained with aniline," benzylamine or n-butylamine. Ivanova has also shown that an A-methylketimine is an effective reagent in the Erlenmeyer azlactone synthesis. Quantitative yield of 19 is generated by treatment of 3 equivalents of 2-phenyl-5(4ff)-oxazolone (2) (freshly prepared in benzene) with 1 equivalent of iV-methyl-diphenylmethanimine (18) in benzene. Products resulting from aminolysis (20), alkali-catalyzed hydrolysis (21), and alcoholysis (22) were also described. 

In 1965, Breslow and Chipman discovered that zinc or nickel ion complexes of (E)-2-pyridinecarbaldehyde oxime (5) are remarkably active catalyst for the hydrolysis of 8-acetoxyquinoline 5-sulfonate l2). Some years later, Sigman and Jorgensen showed that the zinc ion complex of N-(2-hydroxyethyl)ethylenediamine (3) is very active in the transesterification from p-nitrophenyl picolinate (7)13). In the latter case, noteworthy is a change of the reaction mode at the aminolysis in the absence of zinc ion to the alcoholysis in the presence of zinc ion. Thus, the zinc ion in the complex greatly enhances the nucleophilic activity of the hydroxy group of 3. In search for more powerful complexes for the release of p-nitrophenol from 7, we examined the activities of the metal ion complexes of ligand 2-72 14,15). 

The most common reactions of carboxylic acid derivatives are substitution by water (hydrolysis) to yield an acid, by an alcohol (alcoholysis) to yield an ester, by an amine (aminolysis) to yield an amide, by hydride ion to yield an alcohol (reduction), and by an organometallic reagent to yield an alcohol (Grignard reaction). 

Important solvolysis reactions for nylons are hydrolysis, methanolysis, glycolysis, aminolysis, ammonolysis, transamidation, and acidolysis.17 Hydrolysis of nylon-6 with steam in the presence of an acid catalyst to form caprolactam is tlie preferred depolymerization approach. However, when recycling carpet face fibers, file fillers in the polymer may react with file acid catalyst and lower the efficiency of the catalyst. 

Figure 10.4 Four major polyester depolymerization processes (hydrolysis, alcoholysis, acidolysis, and aminolysis).

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