Bases Ethylenediamine

Bases (ethylenediamine, triethylamine, pyridine) were found to be strong sensitizers. Acids (sulphuric acid, acetic acid) were found to be much weaker sensitizers. Dibutyl phthalate, benzene, cyclohexane were found to be weak desensitizers. 

The basis of the reaction is the in situ release of HO-NH2, which together with the HCl acceptor base ethylenediamine forms a second phase above the heavier dichloromethane. The dialkyldichlorosilane is added dropwise and reacts with the hydroxylamine. 

The synthesis of the pure silica form of deca-dodecasil 3R was first described by Gies [22,24] and later adapted by den Exter et al. [20]. A typical molar composition of the synthesis gel is 47 ADA 100 SiO2 404 EN 11240 H2O. Tetra-methylorthosilicate is used as silica source and hydrolyzed through the addition of the base ethylenediamine (EN). The crystallization occurs in glass tubes [22,... 

Figure 5 illustrates the type of encapsulation process shown in Figure 4a when the core material is a water-immiscible Hquid. Reactant X, a multihmctional acid chloride, isocyanate, or combination of these reactants, is dissolved in the core material. The resulting mixture is emulsified in an aqueous phase that contains an emulsifier such as partially hydroly2ed poly(vinyl alcohol) or a lignosulfonate. Reactant Y, a multihmctional amine or combination of amines such as ethylenediamine, hexamethylenediamine, or triethylenetetramine, is added to the aqueous phase thereby initiating interfacial polymerisation and formation of a capsule shell. If reactant X is an acid chloride, base is added to the aqueous phase in order to act as an acid scavenger. 

Ethyleneurea Resins. One of the most widely used resins during the 1950s and 1960s was based on dimethylolethyleneurea [136-84-5] (l,3-bis(hydroxymethyl)-2-imidazohdinone) commonly known as ethyleneurea resin. This resin [28906-87-8] is most convenientiy prepared from urea, ethylenediamine, and formaldehyde. 2-Imidazohdinone [120-93-4] (ethyleneurea) is first prepared by the reaction of excess ethylenediamine [107-15-3] wiih. urea (38) in an aqueous medium at about 116°C. 

A variety of waxy hydrophobic hydrocarbon-based soHd phases are used including fatty acid amides and sulfonamides, hydrocarbon waxes such as montan wax [8002-53-7], and soHd fatty acids and esters. The amides are particularly important commercially. One example is the use of ethylenediamine distearamide [110-30-5] as a component of latex paint and paper pulp blackHquor defoamer (11). Hydrocarbon-based polymers are also used as the soHd components of antifoaming compositions (5) examples include polyethylene [9002-88-4], poly(vinyl chloride) [9002-86-2], and polymeric ion-exchange resins. 

V-[2-Hydroxyethyl]ethylenediamine [2-(2-aminoethylamino)ethanol] [111-41-1] M 104.1, b 91.2°/5mm, 238-240°/752mm, n 1.485, d 1.030, pK 3.75, pK 9.15. Distilled twice through a Vigreux column. Redistilled from solid NaOH, then from CaH2. Alternatively, it can be converted to the dihydrochloride and recrystallised from water. It is then dried, mixed with excess of solid NaOH and the free base distilled from the mixture. It is finally redistilled from CaH2. [Drinkard, Bauer and Bailar 5 Am Chem Soc 82 2992 7960.]... 

Quite a number of mixed sulfur-nitrogen macrocycles have been prepared, but these have largely been by the methods outlined in Chaps. 4 and 5 for the respective heteroatoms. An alternative method, involves the formation of a Schiff base, followed by reduction to the fully saturated system, if desired. An interesting example of the Schiff base formation is found in the reaction formulated in (6.12). Dialdehyde 14 is added to ethylenediamine in a solution containing ferrous ions. Although fully characterized, the yield for the reaction is not recorded. To avoid confusion with the original literature, we note the claim that the dialdehyde [14] was readily prepared in good yield by reaction of the disodium salt of 3-thiapentane-l, 5-diol . The latter must be the dithiol rather than the diol. 

If the final product is prone to D-homo rearrangement during the hydrolysis step, cleavage of the oxalolactone with ethylenediamine instead of inorganic base avoids this complication. ... 

A variety of inorganic (31,87) and organic bases have been added to the catalyst to improve selectivity. The effectiveness of organic bases is very sensitive to structure. Morpholine is an effective inhibitor, more so than /Si-melhylmorphollne > N-elhylmorpholine > 3,5-dimethylmorpholine (55). Piperazine is effective, but ethanolamine and ethylenediamine are poisons. 

Ethylenediamine (15 g, 0 5 mol) was added dropwise to 100 ml 9B-100% formic acid in a two-necked 500 ml flask, fitted with an addition tube and reflux condenser with drying tube, cooled in an ice-bath. After complete addition of the base, 53 g of benzaldehyde (0.5 mol) was added in one lot. The ice-bath was removed and the flask was heated to the refluxing temperature. The initial rate of carbon dioxide evolution was too rapid to measure. After twenty minutes, the rate was circa 100 ml per minute and decreased rapidly to B ml per minute in one hour. Heating at reflux was continued for 35 hours. 

The viscous oil resin Is slurried twice with 250 cc portions of methanol to remove any unreacted primary amines. The oil residue after being washed with methanol is dissolved in ethyl alcohol and 75 cc of concentrated hydrochloric acid is added dropwise to the warm alcohol solution of the base. The dihydrochloride salts of the several hydroabietyl ethylenediamines precipitates immediately from solution. The salt is then separated by filtering and is washed twice with 100 cc portions of cooled ethyl alcohol. The dihydrochloride salts of the dehy-droabietyl, dihydroabietyl and tetrahydroabietyl ethylenediamine mixture have a melting point of about 292°C to 295°C. On subjecting the mixture to solubility analyses it Is found that the dehydroabietyl ethylenediamine is present in substantially the same proportion as is the dehydroabietylamine in the original "Rosin Amine D."... 

Less study has been made of complexes with polydentate ligands. Ag-N linkages have been studied in relation to polynucleotide bases and the Ag-DNA interaction could be important in the use of the silver-sulphadiazine complex in burn treatment. Ethylenediamine is a bridging ligand in AgenC104 (2-coordinate silver) but essentially planar 5-coordination... 

We see from these examples that many of the carbon nucleophiles we encountered in Chapter 10 are also nucleophiles toward aldehydes and ketones (cf. Reactions 10-104-10-108 and 10-110). As we saw in Chapter 10, the initial products in many of these cases can be converted by relatively simple procedures (hydrolysis, reduction, decarboxylation, etc.) to various other products. In the reaction with terminal acetylenes, sodium acetylides are the most common reagents (when they are used, the reaction is often called the Nef reaction), but lithium, magnesium, and other metallic acetylides have also been used. A particularly convenient reagent is lithium acetylide-ethylenediamine complex, a stable, free-flowing powder that is commercially available. Alternatively, the substrate may be treated with the alkyne itself in the presence of a base, so that the acetylide is generated in situ. This procedure is called the Favorskii reaction, not to be confused with the Favorskii rearrangement (18-7). ... 

The abbreviations are derived from the trivial name of the free base, viz.,bis(acetylacetone)ethylenediamine, BAE, bae, seen... 

Bis(ethylenediamine)gold(III) chloride reacts with a variety of -diketonates in aqueous base, via Schiff base condensation, to form 14-membered tetraaza 12jt macrocyclic species [78[. The parent member of the series [AuL ]" being 22 (where H2L = 5,7,12,14-tetramethy]-l,4,8,ll-tetraazacydotetradeca-4,6,ll,13-tetra-ene) (Figure 2.15). The X-ray structure shows the cation to be nearly planar. 

Analysis of Corexit 9527. Corexit 9527 in natural waters can be analyzed. The method is based on the formation of a Z>w(ethylenediamine) copper(II) complex, extraction of the complex into methylisobutylketone, and atomic absorption spectroscopy [1564]. The method is suitable for a concentration range of 2 to 100 mg/liter, with a precision as low as 5% relative to standard deviation for samples in the middle- to high range. Only a small sample volume (10 ml) is required. The sensitivity may be substantially increased for trace analysis by increasing the sample volume. 

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