Nitrogen compounds carboxylates

Challis, B. and Challis, J. (1979). Amides and related compounds. In Comprehensive Organic Chemistry, Nitrogen Compounds, Carboxylic Acids, Phosphorous Compounds, Sutherland, I.O. (ed.), Vol. 2, p. 957. Pergamon Press, Oxford... 

J. S. Roberts in D. Barton u. W.D. Ollis, Comprehensive Organic Chemistry, The Synthesis and Reactions of Organic Compounds, Bd. 2 in O. Sutherland, Nitrogen Compounds, Carboxylic Acids, Phosphorous Compounds, S. 185ff., Pergamon Press, Oxford 1979. 

J. R. Malpass, in Comprehensive Organic Chemistry D. Barton, W. D. Ollis, eds., Vol. 2 Nitrogen Compounds, Carboxylic Acids, Phosphorus Compounds, I. O. Sutherland, ed., Pergamon, New York, 1979, p. 47. 

POLYAMIDE. Separations are based on formation of hydrogen bonds between the functional groups of the sample (phenols, amino acid derivatives, heterocyclic nitrogen compounds, carboxylic and sulfonic acids) and the carbonyl oxygen of the amide group, as well as a general reversed-phase partition mechanism (water is the weakest solvent). Available as two polycondensation products, polyundecanamide (PA 11) and polycaprolactam (PA 11). 

Fluorocarbon nitrogen compounds Carboxylic acid bis(trifluoromethyl)amides from carboxylic acid chlorides... 

This intermediate attacks compounds containing a variety of functional groups, such as primary, secondary, and tertiary amino nitrogen atoms, carboxyl groups, and sulfhydryl groups (10). 

Oxidative reactions frequently represent a convenient preparative route to synthetic intermediates and end products This chapter includes oxidations of alkanes and cycloalkanes, alkenes and cycloalkenes, dienes, aromatic fluorocarbons, alcohols, phenols, ethers, aldehydes and ketones, carboxylic acids, nitrogen compounds, and organophosphorus, -sulfur, -selenium, -iodine, and -boron compounds... 

Azetidine-2-carboxylic acid, the lower homolog of proline, has been isolated from Convallaria majalis (lily of the valley) 40,44), Polygonatum officinalis (Solomon s seal) 153), and Polygonatum multiflorum 45). Fowden and Steward 47) surveyed plants from 56 genera for nitrogenous compounds and found azetidine-2 -carboxylic acid to be restricted to members of the Liliaceae. In some species it was identified in leaf, stem, and root but was more commonly found in the seed. In Polygonatum, azetidine-2-carboxylic acid accounted for 75% or more of the total nonprotein nitrogen in the rhizome 45). There was no evidence that it occurred as a constituent of protein. 

Rhenium(VI) complexes, 4,194 alkoxides, 4,196 amides, 4,194 amines, 4,199 carboxylates, 4,199 dimethylformamide, 4,199 dioxane, 4,198 halides, 4,195,199 2-hydroxypyridine, 4,199 imides, 4,194 magnetic behavior, 1,271 mixed sulfur-nitrogen compounds, 4,196 N heterocycles, 4,199 nitrides, 4,194 oxide halides, 4, 195 oxoanions,4,196 pyridine, 4,199 sulfates, 4,198 sulfur compounds, 4,196 tellurates, 4,198... 

Proteins are also important nitrogen compounds. They constitute much of the cell materials, and are present in every type of organism known. In humans, muscle tissue, skin, and hair is mostly protein, about half of the dry weight of our bodies. From a chemical point of view, proteins are polymers of amino acids, alpha amine derivatives of carboxylic acids. Only about 20 different amino acids are actually found in proteins. It is the large number of variations in the protein chain, using only these... 

E. L. Shock (1990) provides a different interpretation of these results he criticizes that the redox state of the reaction mixture was not checked in the Miller/Bada experiments. Shock also states that simple thermodynamic calculations show that the Miller/Bada theory does not stand up. To use terms like instability and decomposition is not correct when chemical compounds (here amino acids) are present in aqueous solution under extreme conditions and are aiming at a metastable equilibrium. Shock considers that oxidized and metastable carbon and nitrogen compounds are of greater importance in hydrothermal systems than are reduced compounds. In the interior of the Earth, CO2 and N2 are in stable redox equilibrium with substances such as amino acids and carboxylic acids, while reduced compounds such as CH4 and NH3 are not. The explanation lies in the oxidation state of the lithosphere. Shock considers the two mineral systems FMQ and PPM discussed above as particularly important for the system seawater/basalt rock. The FMQ system acts as a buffer in the oceanic crust. At depths of around 1.3 km, the PPM system probably becomes active, i.e., N2 and CO2 are the dominant species in stable equilibrium conditions at temperatures above 548 K. When the temperature of hydrothermal solutions falls (below about 548 K), they probably pass through a stability field in which CH4 and NII3 predominate. If kinetic factors block the achievement of equilibrium, metastable compounds such as alkanes, carboxylic acids, alkyl benzenes and amino acids are formed between 423 and 293 K. 

The OPLS parameters (charges and Lennard-Jones terms) were obtained primarily via Monte Carlo simulations with particular emphasis on reproducing the experimental densities and heats of vaporization of liquids. Those simulations were performed iteratively as part of the parametrization, so better agreement with experiment is obtained than in previous studies where the simulations were usually carried out after the parametrization. Once the OPLS parametrization was completed, further simulations were also performed in order to test the new set of parameters in the calculation of other thermodynamic and structural properties of the system, besides its density and its heat of vaporization. Parameters have now been generated, among others, for water, alkanes, alkenes, alcohols, amides, alkyl chlorides, amines, carboxylic esters and acids, various sulfur and nitrogen compounds, and nitriles. A protein force field has been established as well. 

Fig. 20.6 shows the trend in consumption for the three most important types of herbicides. Carboxylic acids have been the standby for many years and were the first type of herbicide. They were replaced as number one by the heterocyclic nitrogen compounds in the 1970s. Carboxylic acids are making a comeback in the 1990s. A close third are the amide herbicides. The present percentage of consumption for herbicides is given in Table 20.7. 

Thus, the hydrodesulfurization process is a very complex sequence of reactions due, no doubt, to the complexity of the feedstock. Furthermore, the fact that feedstocks usually contain nitrogen and oxygen compounds (in addition to metal compounds) increases the complexity of the reactions that occur as part of the hydrodesulfurization process. The nitrogen compounds that may be present are typified by pyridine derivatives, quinoline derivatives, carbazole derivatives, indole derivatives, and pyrrole derivatives. Oxygen may be present as phenols (Ar-OH, where Ar is an aromatic moiety) and carboxylic acids (-C02H). The most common metals to occur in petroleum are nickel (Ni) and vanadium (V) (Reynolds, 1997). 

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