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Ethanolamine, basicity

Corti and Manfrida [2] have also done detailed calculations of the performance of plant A2. They drew attention to the need to optimise the amines blend (including species such as di-ethanolamine and mono-ethanolamine) in the absorption process, if a removal efficiency of 80% is to be achieved and in order to reduce the heat required for regenerating the scrubbing solution. Their initial estimates of the penalty on efficiency are comparable to those of Chiesa and Consonni (about 6% compared with the basic CCGT plant) but they emphasise that recirculation of water from... [Pg.146]

A large number of nitramine-based explosives have been synthesized via Mannich-type condensation reactions (Section 5.13.2). The amines generated from these reactions often have the powerful electron-withdrawing trinitromethyl or fluorodinitromethyl groups positioned on the carbon a to the amino group. This reduces amine basicity to an extent that A-nitration becomes facile. The energetic nitramines (17), (19) and (21) have been synthesized from the condensation of ethylenediamine with 2,2,2-trinitroethanol, 2-fluoro-2,2-dinitroethanol with ethanolamine, and 2-fluoro-2,2-dinitroethylamine with 2,2-dinitro-l,3-propanediol respectively, followed by A-nitration of the resulting amine bases (16), (18) and (20), respectively. [Pg.196]

Acylation of the theophylline diamine intermediate (26-6) with phenylacetyl chloride affords the corresponding amide (28-2). Base catalyzed cyclization then leads to the purine (28-3) that now includes a quite lipophilic benzyl group on the fused imidazole ring. The molecule is then provided with a side chain that incorporates basic nitrogen, arguably to improve water solubility. The anion from (28-3) is thus first alkylated with bromochloroethane to afford the chloroethyl product (28-4). The displacement of chlorine with ethanolamine affords the bronchodilator bamifylline (28-5) [28]. [Pg.595]

Ethanolamine nitric ester nitrate (ethanolamine dinitrate) N03NH3CH2CH20N02 is a solid melting at 103°C. According to Naoum this compound can be prepared by nitrating ethanolamine [68], Aubry [69] has reported that a yield of 90-96% can be achieved in this reaction. This method of preparation has not been confirmed by some authors. Serious disadvantages of the substance include its inclination to absorb moisture, and the readiness with which it loses nitric acid owing to the wealdy basic properties of the amine [70],... [Pg.472]

SYNTHESIS To a well stirred solution of 25 g ethanolamine hydrochloride in 75 mL MeOH there was added 4.45 g of 3,4-methylenedioxyphenylacetone (see under MDMA for its preparation) followed by 1.1 g sodium cyanoborohydride. Concentrated HC1 in MeOH was added as required, over the next few days, to maintain the pH at about 6 as determined with external, dampened universal pH paper. The reaction mixture was added to 300 mL HjO and made strongly acidic withanexcessofHCl. Afterwashing with 3x100 mL CH2Q2 the aqueous phase was made basic with 25%... [Pg.375]

Table 9.13 summarizes the effect of the kind of reductant on the photochromic behavior of thionine dye. All reductants afforded transparent films upon irradiation and complete color recovery in the dark. The greatest photosensitivity was obtained with TEA as the reductant. The reversibility decreased in the order, tri->di->mono-ethanolamine. The difference cannot be explained by an electron-donating character such as the basicity of the reductant (P A a value of their ammonium salt tri-mono-ethanolamine). A potential explanation is that TEA(bp, 335.4°C/760mmHg) is so hygroscopic that the moisture absorbed in TEA and TEA itself acts as a plasticizer, providing tough films that afford higher color reversibility, as mentioned earlier. [Pg.365]

Myelin is modified plasma membrane. Myelin of the PNS resembles that of the CNS with respect to lipid composition. There is an enrichment in such specialized lipids as cerebroside and ethanolamine plasmalogen, and the high content of cholesterol plays an important role in control of membrane fluidity. The protein composition of PNS myelin is, however, distinct from that of CNS myelin. A single protein, P0, accounts for half of all protein of PNS myelin. Of the other proteins present, most are expressed in the CNS as well as the PNS but in quantitatively different amounts. Prominent among these proteins are myelin basic proteins and myelin-associated glycoprotein. [Pg.732]

The reduction is bimolecular and thus the rate is dependent on concentration. Running the reaction neat provides the fastest rates. Usually an excess of Alpine-Borane is used to insure that the reaction does not become excessively slow at the end of the reduction. The excess organoborane may be destroyed by addition of an aldehyde such as Acetaldehyde. The resulting alkoxy-9-BBN may be treated with Ethanolamine to liberate the alcohol and precipitate the majority of the 9-BBN. Any remaining borane impurities may be removed by oxidation with basic Hydrogen Peroxide. [Pg.478]

Ethylenediamine (en), NH2C2H4NH2, a strongly basic substance, may be considered to represent solvents that are weakly acidic compared with water. Ethylenediamine is therefore useful as a solvent for the titration of weakly acidic substances. It is a leveling solvent for adds whose ionization constants are larger than about 10 in water thus acetic add and hydrochloric acid are leveled to about equal strength. The titrant base normally used in en is sodium ethanolamine. The autoprotolysis constant of en is 5 x 10" for the equilibrium... [Pg.74]

Amphiprotic protogenic solvents have higher acidic properties, but lower basic ones (always in comparison to water). Examples are formic and acetic acid. Amphiprotic protophilic solvents have lower acidity and higher basicity than water, with formamide or ethanolamine as examples. Aprotic dipolar solvents have low acidity and (occasionally) basicity as well, with A,A-dimethylformamide and dimethylsulfoxide as examples for protophilic dipolar solvents and acetonitrile for a protophobic dipolar solvent. [Pg.400]

A typical profile for hybridoma cells includes the ITS mixture and the small molecules ethanolamine and (3-mercaptoethanol. There are many variations of this basic profile, each specific for the particular hybridoma line and nutrient medium used. [Pg.95]

The reaction of trimellitic anhydride (7) with ethanolamine (9) giving the hydroxy acid (10) and with 4,4 -diaminodiphenylmethane (8) giving the diacid (11) has been published in the first poly(ester-imide) patent [l].The second one is nowadays the predominant reaction for making poly(ester-imide)s. Trimellitic anhydride is the basic dianhydride for introducing the imide structure into the polyesters. Nearly every example in patents is based on trimellitic anhydride alone or mixtures with other anhydrides, e.g., tetrahydrophthalic anhydride [59]. The imides made from aromatic anhydrides are thermally more stable than the ones resulting from aliphatic structures (Fig. 4). Both types have been protected by patents, and products made from them are on the market. [Pg.52]

Polyurethane chemolysis by reaction with ammonia or various amines has been described in the literature. Sheratte92 has proposed a process based on polyurethane decomposition by various agents. Several examples were provided for polyurethane degradation with ethanolamine (120 °C), ammonia and ammonium hydroxide (180 °C), diethylene triamine (200 °C) and other basic reagents. In all cases the process involves, simultaneously or subsequently, reaction with propylene oxide, which allows the different amines obtained to be quantitatively converted into polyols according to the reaction shown in Scheme 2.6. The polyols derived from this process were used in the reformulation of new polyurethanes by polymerization with the corresponding isocyanate, and were suitable for application in rigid foams. [Pg.49]

On the one hand, alternative basic deprotection cocktails were developed using various combinations of hydrazine, ethanolamine, and alcohol [146] or incorporating the use of more nucleophilic alkylamines [7,16]. The latter method favors 40% aqueous methylamine in place of or in addition to 30% ammonium hydroxide, which cleaves the acyl protecting groups present on the nucleobases in a few minutes at 65°C or in over 1 h at room temperature. [Pg.509]


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See also in sourсe #XX -- [ Pg.178 ]




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Ethanolamines

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