What reagent are you using to hydrolyze the amide?
Hydrolysis
Hydrolysis is defined as the ester bond decomposition due to the moisture and water which leads to a meaning (melt) viscosity and molecular weight subtract.
From: Multilayer Flexible Packaging , 2010
Chemical reactions used in analytical derivatizations
Serban Moldoveanu , Victor David , in Modern Sample Grooming for Chromatography (Second Edition), 2021
Hydrolysis
Hydrolysis is a mutual reaction in the analysis of a number of compounds such every bit derivatives of organic acids or in the analysis of polymers. Because hydrolysis is a chemical modification of the analyte, it can be seen as a derivatization. Typically hydrolysis is followed by a second derivatization that creates a compound with improve belittling properties such as higher detectability or with no active hydrogens. For large molecules such as proteins or polysaccharides, hydrolysis is frequently practical to generate fragments easier to clarify, and the subject is presented in Chapter fourteen. Certain pocket-sized molecules such as anhydrides, acyl chlorides, amides, and nitriles can exist subjected to hydrolysis before further derivatization or assay.
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Analysis, Removal, Effects and Hazard of Pharmaceuticals in the Water Cycle
Guang-Guo Ying , ... Shan Liu , in Comprehensive Analytical Chemical science, 2013
two.2.ii Hydrolysis
Hydrolysis is some other important process for some pharmaceuticals in the aquatic environs ( Tables iv–6). But not all pharmaceuticals can be hydrolyzed in water. For example, steroids and acidic drugs cannot undergo hydrolysis.
For antibiotics, hydrolysis is a significant process for their fate in the aquatic environment. For sulfonamides, an acidic pH solution is virtually favorable to hydrolysis, followed by neutral and element of group i solutions [131]. A ascent in solution temperature increases the hydrolysis of sulfonamides, just degradation is still low. On acidic hydrolysis, the sulfonamide bail breaks to produce sulfanilic acid and the appropriate amino derivatives every bit the common degradation products [7]. However, some sulfonamides (e.g., sulfachlorpyridazine, sulfadimethoxine, and sulfathiazole) are recalcitrant to hydrolysis at lower temperatures (seven, 22, and 35 °C; pH 2, 5, seven, and 9) and crave loftier concentrations of potent acids or bases [73]. Thus, under typical environmental conditions, sulfonamides are hydrolytically stable with a long half-life.
Tetracyclines are sensitive to hydrolysis [73,82]. The hydrolysis of oxytetracycline, chlortetracycline, and tetracycline is influenced by such factors as temperature and pH value [73]. However, fluoroquinolones are insensitive to hydrolysis [9]. Pouliquen et al. [82] reported that oxolinic acid and flumequine were not hydrolyzed in 3 types of water (deionized water, freshwater, and seawater).
Many macrolides are weak bases and unstable in acid [9]. Hydrolysis was observed at pH 2 and 11 for tylosin, but not at 5, vii, or 9 [73]. Hydrolysis rates for macrolides in the presence of iron (III) were low with their one-half-lives calculated to be 1.99 and 2.67 days for roxithromycin and clarithromycin, respectively [93].
Florfenicol is not degradable by hydrolysis or photolysis [82]. Trimethoprim and lincomycin cannot exist degraded by hydrolysis either [73]. But for β-lactams, β-lactam ring is hands cleaved in acidic and basic media [ix].
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THE FATE OF XENOBIOTICS IN LIVING ORGANISMS
Franz M. Belpaire , Mark K. Bogaert , in The Practice of Medicinal Chemistry (Second Edition), 2003
Hydrolysis.
Hydrolysis of esters and amides is a common pathway of drug metabolism. The liver microsomes contain non-specific esterases, as do other tissues and plasma. Hydrolysis of an ester results in the formation of an booze and an acid; hydrolysis of an amide results in the formation of an amine and an acrid. The ester procaine, a local anaesthetic, is rapidly hydrolysed past plasma cholinesterases and, to a lesser extent, by hepatic microsomal esterase. An example of an amide which is hydrolysed, is the antiarrhythmic drug procainamide. Enalapril, a prodrug, is hydrolysed by esterases to the active metabolite enalaprilate, which inhibits the angiotensin-converting enzyme.
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Carboxylic Acid Derivatives
Robert J. Ouellette , J. David Rawn , in Organic Chemistry (Second Edition), 2018
Hydrolysis of Amides
Hydrolysis of an amide breaks the carbon–nitrogen bond and produces a carboxylic acid and either ammonia or an amine. The reaction resembles ester hydrolysis, merely there are of import differences. Ester hydrolysis occurs relatively hands, only amides resist hydrolysis. Under acrid conditions, half dozen M HCl and refluxing for 24 hours are required. Under basic conditions, a 40% solution of sodium hydroxide is used. Under these conditions, the salt of a carboxylate anion is produced. As in saponification of esters, an acrid–base reaction to form the carboxylate anion pulls the reaction to completion.
When amide hydrolysis is carried out under acid weather, the ammonium salt of the amine forms, and a mole of acrid reacts with each mole of the amide. The formation of the conjugate acid of the amine drives the reaction to completion. The free amine forms in a subsequent neutralization reaction with base.
The stability of amides has of import biochemical consequences because the amino acrid residues in proteins are linked by amide bonds. Considering amides are stable, proteins exercise not hydrolyze at physiological pH and body temperature without an enzyme catalyst.
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Natural Deposition on Plastics and Corrosion of Plastics in Industrial Environment
Anand Sawroop Khanna , in Reference Module in Materials Science and Materials Engineering, 2021
Corrosion of Plastics by Chemicals
Corrosion of plastics is quite different in comparison to metal corrosion. Comparing steel to a simple plastic, corrosion in steel tin exist minimized by awarding of a blanket, or using cathodic protection or by the use of some inhibitor chemicals in the solution in the container. In plastics, information technology is not possible to protect past any of the given methods used in steel but still it is possible to create high functioning plastics which can resist strong acids, alkalies or several toxic organic solvents and chemicals. By choosing the correct polymer family, it is possible to cull a plastic which can withstand even the harshest ecology conditions without the need for additional protection such every bit surface treatment, painting or cathodic protection. Tabular array 1 gives a list of various plastics which testify resistant to a potent and weak acids, alkalies, solvents and polar organic solvents.
Table 1. Compares corrosion resistance of various plastics in acids and alkalies (come across "Relevant Websites section")
| Commercial proper noun of plastic | Structural formula (Grouping) | Depression pH compatibility | Loftier pH compatibility |
|---|---|---|---|
| TECAFINE PE, PP | Polyethylene & Polypropylene | 0.five | 13.5 |
| TECAFORM AH a | Acetal co-polymer | iv | 13 |
| TECAFORM AD | Homopolymer with PTFE fiber | 4 | nine |
| TECAMID, TECAST a | Crystalline Polyamide, Nylon half-dozen | four | 12 |
| TECAPET | PET | i | 9 |
| TECAFLON PVDF b | PVDF | 0.5 | thirteen.5 |
| TECAFLON PTFE a | PTFE | 0.v | 13.5 |
| TECATRON | PPS | 0.5 | 13.v |
| TECAPEEK a | PEEK | 0.5 | thirteen.5 |
Note: #Glass cobweb reinforced grades testify a slightly lower resistance to strong alkalies compared to unfilled grades.
**PVDF reacts sensitively to contact with hot alkalies past causing stress cracks when exposed to mechanical stress. The exposure limits are
pH 12 and 40°C, neither one of which may be exceeded.
- a
- Resistant.
- b
- Limited Resistant.
Hydrolysis of plastics takes place in acidic or basic water to give lower molecular weight molecules. For example polymers similar polyesters, polyamides and polycarbonates can be degraded by hydrolysis. Polyamide is sensitive to degradation past acids and will crevice when attacked by potent acids. For instance, the fracture surface of a fuel connector showed the progressive growth of the crack from acid attack, known equally stress corrosion dandy, and in this example was acquired by hydrolysis of the polymer. It was the contrary reaction of the synthesis of the polymer:
(xiv).
Chemical resistance is highly dependent on the molecule structure of a polymer as for thermoplastics, whether they are baggy (eastward.g., PC, PVC, PS, PMMA) or partially crystalline (east.g., PE, PA, PP, POM). Partially crystalline are more resistant to organic substances and solvents than baggy polymers. Thermosetting resins (e.g., PUR, EP, Upwardly) can, due to their cross-linked structure not be dissolved, but tin can be subjected to swelling or chemical reaction (e.g., hydrolysis).
Physical effects on polymers are caused past interaction with the environment. This may lead to swelling, dissolving or leakage of additives. The interaction is dependent on diffusion of substances into the polymer, and the process is in some cases reversible.
Organic substances ordinarily affect polymers through physical interaction, while substances similar stiff acids or bases normally result in an irreversible breakdown of polymers.
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Poly(alkylene H-phosphonate)south
Kolio Dimov Troev , in Polyphosphoesters, 2012
Dependence of Hydrolysis on the PEG Segment Length
Hydrolysis of polymers A, B, and C was performed under neutral conditions at the same concentrations (ane.23×10 –3 and 7.29×x–3 K). The results from 31P{H} NMR analysis are graphically presented in Figures 1.xviii and 1.19 and reveal a like pattern to that shown in the previous section.
Figure one.18. Degree of hydrolysis of PEO-H-P A, B, and C versus time at concentration of i.23×10–3 M and pH=7.4, obtained past 31P{H} NMR at 37°C.
Figure 1.19. Degree of hydrolysis of PEO-H-P A, B, and C versus time at concentration of seven.29×10–3 M and pH=7.4, obtained by 31P{H} NMR at 37°C.
It tin be seen that hydrolysis of all POE-H-Ps at neutral conditions is affected in a like fashion by their initial concentration. Independently of the POE segment length, a departure of most 70% in the degree of hydrolysis is observed upon a sixfold increase in the starting concentration of the polymer (Figures 1.18 and one.19). In both concentrations, PEO-H-P A shows a 10–12% higher degree of hydrolysis with respect to POE-H-Ps B and C. The slightly better hydrolytic stability of polymers B and C can exist attributed to the relatively lower weight content of hydrolyzable groups.
The initial phase of hydrolysis involved cleavage of the alkoxy cease groups. The rate of hydrolysis of the end alkoxy groups was higher than that of P
OC bonds in the repeating unit. A 31P{H} NMR study of the hydrolytic stability of poly(oxyethylene H-phosphonate) showed that the degree of hydrolysis after half dozen h at acid pH is near 20% and at basic pH is 36%. This effect tin can be explained by the assemblage of poly(oxyethylene H-phosphonate), which prevents further hydrolysis of the polymer. An aqueous SEC study of poly(oxyethylene H-phosphonate)s showed predominant self-associates of these polymers in water [111]. Apparently, the acidic POH groups, formed as a outcome of hydrolysis of the POC bond, participate in hydrogen bonding with P
O groups, resulting in the formation of aggregates. At elevated temperatures, the final products of hydrolysis were H-phosphonic acid and the starting hydroxyl-containing chemical compound.
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Fluorescence | Fluorescence Derivatization☆
Marta E. Díaz-García , Rosana Badía-Laíño , in Encyclopedia of Analytical Science (Third Edition), 2019
Hydrolysis Reactions
Hydrolysis is one of the well-nigh simple treatment methods to convert nonfluorescent compounds to fluorescent ones. Information technology is commonly accomplished in a strongly alkaline aqueous medium and, in some cases, at a loftier temperature, resulting in the formation of fluorescent anions. Thus, acetylsalicylic acid (aspirin) has weak native fluorescence, but its base-hydrolysis cohabit, the salicylate ion, strongly fluoresces at ∼ 400 nm after it has been excited at about 310 nm. This holding has been used to determine aspirin and salicylates directly in serum, urine, and plasma samples. In the same way, hydrolysis has been successfully practical to the determination of carbamate pesticides and organo-phosphorus insecticides, with detection limits in the low nanogram range. The sensitivity could be improved after estrus treatment of the hydrolysis products even for many pesticides.
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Stationary Phases and Their Performance
Serban C. Moldoveanu , Victor David , in Essentials in Modern HPLC Separations, 2013
Directly Synthesis of Silica Materials with an Agile Bonded Phase Surface
Derivatized silica surfaces also tin be obtained direct through hydrolysis of the appropriate reagents, without having bare active silica prepared as a get-go step, followed by further derivatization. For example, the hydrolysis of tetramethyl orthosilicate (tetramethoxysilane or TMOS) in the presence of octyltrimethoxysilane in an acidic medium generates a silica gel that contains octyl groups attached to the silica construction. The same procedure can be applied to obtain silica having C18 bondage attached on its surface. Another example of direct reaction for obtaining a functionalized silica surface is the training of propylsulfonic acid functionalized mesoporous silica. This material tin can be prepared in a unique step starting with tetraethyl orthosilicate, 3-mercaptopropyltrimethoxysilane, and H 2Otwo, in stiff acidic conditions [57].
Direct hydrolysis of a mixture of silane derivatives (co-hydrolysis) may generate the desired functional groups on the silica surface, just it can also make the process more difficult to control particularly in relation to the size and shape of stationary phase particles [58]. For this reason, co-hydrolysis has been used more frequently for preparation of monolith-type materials where the control of particle size is not a disquisitional step. The process leads to so-called organic-inorganic monoliths. One example of co-hydrolysis reaction is given in half-dozen.2.16:
(6.ii.xvi).
In reaction half-dozen.2.16, the radical R tin can be octyl or octadecyl, but also other radicals. The procedure is also utilized for preparing monoliths with mixed-mode functionalities. For example, a mixture of tetramethoxysilane (TMOS), aminopropyltrimethoxysilane, and octyltrimethoxysilane can be hydrolyzed in acidic medium to generate a monolith with the active surface covered with both octyl and aminopropyl groups. In a similar manner, a mixed-mode phase having octyl and cyano groups can be prepared, starting with tetramethoxysilane (TMOS), cyanopropyl-trimethoxysilane, and octyltrimethoxysilane [59]. Both structures are schematically shown in Figure 6.2.v.
Effigy half dozen.two.5. Schematic construction of a mixed style phase with octyl and amino groups and a phase with octyl and cyano groups.
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The material backdrop of geosynthetics
S.Due west. Perkins , in Geosynthetics in Civil Technology, 2007
two.half-dozen.three Hydrolysis
Hydrolysis is a process by which a chemical compound decomposes by its reaction with h2o. Geotextiles can feel hydrolysis degradation by internal or external yarn degradation ( Hsuan et al., 1993), which becomes more than significant for polyester materials and for liquids with a loftier alkalinity. Polyamides can be affected by liquids with very low pH values. To evaluate the consequence of hydrolysis, simple tests are conducted where a cloth is immersed in a liquid having a pH level of interest and at temperatures of twenty °C and 50 °C. The strength of the material is determined after a certain corporeality of immersion time and compared with initial values to detect degradation levels.
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