Ethylenediamine, solvent

E16.6 Anionic species such as 4 and Te3 are intrinsically basic species that cannot be studied in st vents that are Lewis acids because complex formation (the Lewis acid-base pair) will destroy the independent identic of the anion. Since the basic solvent ethylenediamine will not react with Na2S4 or with K2Tej, it is a better solvent for them than sulfur dioxide. 

Semiconducting nanorods and nanowires were synthesized by y-irradiation at room temperature and the atmospheric pressure. The experiment was carried out in ethylenediamine and pyridine as solvents. Ethylenediamine (en) and pyridine (py) molecules were coordinated with metal ions and had an effect on the shape like nanorods and nanowires (Jo et al. 2006). Semiconducting nanorod and pearl necklace-like nanowire of CdS and CdSe were successfully synthesized by irradiation with a dose of 90 kGy at room temperature and the atmospheric pressure. When nanorods and nanowires were prepared in en and py, the solvent molecules controlled their morphology. From XRD data, the synthesized CdS and CdSe could be observed on the information of crystallinity of them. In nanorod CdS and CdSe, the intensity of the (0 0 2) diffraction peak was extraordinarily strong. This result indicates that the CdS obtained in py have a preferential [0 0 1] orientation. TEM images displayed rod and pearl necklace like morphology with diameters of several nanometers and lengths of upto several microns. For the shape control, en and py were successfully used to replace the surfactant molecules on the surface of nanoparticles. 

Figure 9.12. Dependence of crmcentration (in molar parts) of solvate forms Li(EDA) S on molar fraction, x, of the second component in the binary solvents ethylenediamine-DMSO (a) and ethylenediamine-DMFA (b) 1-m=4, n=0 2- m=n=2 4-m=0, n=4.

An example of applieation of this method is in the work. Authors have calculated relative eoncentration of different solvate forms of LT in the mixed solvent ethylenediamine -DMSO and ethylenediamine-DMFA (Figure 9.12). Free energy of lithium transfer from DMSO (DMFA) in the mixed solvent has been ealeulated from the time of spin-lattice relaxation of kernel Li. The curves presented in Figure 9.12 depict quantitatively the selectivity of LL relative to ethylenediamine, whieh is more basie component in contrast to the second components of the mixed solvent, namely DMSO and DMFA. 

Lithium Acetylide. Lithium acetyhde—ethylenediamine complex [50475-76-8], LiCM7H -112X01120112X112, is obtained as colodess-to-light-tan, free-flowing crystals from the reaction of /V-lithoethylenediamine and acetylene in an appropriate solvent (131). The complex decomposes slowly above 40°O to lithium carbide and ethylenediamine. Lithium acetyhde—ethylenediamine is very soluble in primary amines, ethylenediamine, and dimethyl sulfoxide. It is slightly soluble in ether, THF, and secondary and tertiary amines, and is insoluble in hydrocarbons. 

Bisamides. Methylenebisamides are prepared by the reaction of the primary fatty amide and formaldehyde in the presence of an acid catalyst. AijAT-Methylenebisoleamide has been made via this route without the use of refluxing solvent (55). Polymethylenebisamides can be made from fatty acid, esters, or acid haUdes with diamines while producing water, alcohol, or mineral acid by-products. Eatty acids and diamines, typically ethylenediamine, have been condensed in the presence of NaBH and NaH2P02 to yield bisamides (56). When stearic acid, ethylenediamine, and methyl acetate react for 6 h at... 

Planar-octahedral equilibria. Dissolution of planar Ni compounds in coordinating solvents such as water or pyridine frequently leads to the formation of octahedral complexes by the coordination of 2 solvent molecules. This can, on occasions, lead to solutions in which the Ni has an intermediate value of jie indicating the presence of comparable amounts of planar and octahedral molecules varying with temperature and concentration more commonly the conversion is complete and octahedral solvates can be crystallized out. Well-known examples of this behaviour are provided by the complexes [Ni(L-L)2X2] (L-L = substituted ethylenediamine, X = variety of anions) generally known by the name of their discoverer I. Lifschitz. Some of these Lifschitz salts are yellow, diamagnetic and planar, [Ni(L-L)2]X2, others are blue, paramagnetic, and octahedral, [Ni(L-L)2X2] or... 

Abbreviations acac, acetylacetonate Aik, alkyl AN, acetonitrile bpy, 2,2 -bipyridine Bu, butyl cod, 1,5- or 1,4-cyclooctadiene coe, cyclooctene cot, cyclooctatetraene Cp, cyclopentadienyl Cp, pentamethylcyclopenladienyl Cy, cyclohexyl dme, 1,2-dimethoxyethane dpe, bis(diphenyl-phosphino)ethane dppen, cis-l,2-bis(di[Atenylphosphino)ethylene dppm, bis(diphenylphosphino) methane dppp, l,3-bis(diphenylphosphino)propane eda,ethylenediamine Et,ethyl Hal,halide Hpz, pyrazole HPz, variously substituted pyrazoles Hpz, 3,5-dimethylpyrazole Me, methyl Mes, mesityl nbd, notboma-2,5-diene OBor, (lS)-endo-(-)-bomoxy Ph, phenyl phen, LlO-phenanthroline Pr, f opyl py, pyridine pz, pyrazolate Pz, variously substituted pyrazolates pz, 3,5-dimethylpyrazolate solv, solvent tfb, tetrafluorobenzo(5,6]bicyclo(2.2.2]octa-2,5,7-triene (tetrafluorobenzobanelene) THE, tetrahydrofuran tht, tetrahydrothicphene Tol, tolyl. 

A modification of the preceding preparation employs ethylenediamine as a convenient nonvolatile solvent and Tetralin as the commercially available starting material. The results of the reduction are essentially identical. 

After cooling, unreacted ethylenediamine is neutralized in a cooling mixture with the absolute ethanolic hydrochloric acid, filtered off from any components that are insoluble in ethanol and approximately two-thirds of the solvent filtered off under suction in a water jet pump vacuum. Residual quantities of ethylenediamine dihydrochloride are precipitated in fractions by the careful addition of ethyl methyl ketone, after which the imidazoline hydrochloride is separated off by the addition of dry ether. Following repeated recrystallization from ethanol ether, 2-[0(-(2,6-dichlorophenoxy)ethyl] -A -imidazoline hydrochloride is obtained in the form of small white crystals melting at 221°C to 223°C. 

Even though both ligands form Ni — N bonds of similar strength, ethylenediamine binds to Ni many orders of magnitude more strongly than does NH3. Why is this Think about complexation at the molecular level. One of the Ni — N bonds in either complex can be broken fairly easily. When this happens to [Ni (NH3)g, the ammonia molecule drifts away and is replaced by another ligand, t q)ically a water molecule from the solvent ... 

The presence of ligands, either in the form of added anions such as acetate or as co-solvents or solvents, such as pyridine, markedly affect the kinetics. In pyridine or dodecylamine solvents the hydrogenation of Ag(I) acetate follows simple second-order kinetics, as does that of Cu(I) acetate. This behaviour is also shown in aqueous solutions by Ag(I) in the presence of acetate ions and by an ethylenediamine complex of Ag(I) . The rate of hydrogenation of Cu(II) acetate, on the other hand, is independent of oxidant concentration. The rate of oxidation of hydrogen by Cu(II) acetate in quinoline is also independent of oxidant concentration , but does depend on the square of the concentration of cuprous acetate which acts as a catalyst. For further details of these complicating features, reference should be made to the original papers and to Hal-pern s review ... 

Fig. 4.1. Potential ranges of solvents, (a) h.n.p.s of acids. I, Acetic acid II, benzoic acid III, formic acid IV, salicylic acid V, sulphuric acid VI, p-toluenesulphonic acid, (b) h.n.p.s of conjugate acids of I, n-butylamine II, piperidine III, ethylenediamine (1) IV, ammonia V, ethylenediamine (2) VI, pyridine.

C. (1S,2S)-(-)- and (1 R,2R)-(+)-1,2-Diphenyi-1,2-ethylenediamine (Note 11). A 1 -L, round-bottomed flask equipped with a mechanical stirrer is charged with 42.5 g (0.200 mol) of the racemic diamine and 230 mL of ethanol (Note 9). The solids are dissolved by heating the mixture to 70°C whereupon a hot (70°C), homogeneous solution, of 30.0 g (0.200 mol) of (L)-(+)-tartaric acid (Note 12) in 230 mL of ethanol is added (Note 13). The tartrate salts precipitate immediately, and after the mixture is cooled to ambient temperature, the crystals are collected by filtration, washed twice with 60 mL of ethanol, and dried under reduced pressure. The solids are dissolved in 230 mL of boiling water, 230 mL of ethanol is added and the homogeneous solution is allowed to cool slowly to room temperature. The crystals are collected by filtration, washed with 40 mL of ethanol and dried under reduced pressure. The recrystallization procedure is then repeated twice using the same volumes of solvents (230 mL of water and 230 mL of ethanol) to give 23-25 g (63-69%) of the tartrate salt... 

By dissolving sodium in ethylenediamine and adding this complexing agent (known as a cryptand) followed by evaporation of the solvent, it has been possible to recover a solid that contains Na+(crypt)NaA This shows that although it is rather rare, it possible for Na to complete the 3s level. Of course, this type of behavior also occurs when H is formed. 

Parco et al. described a copper-catalyzed amidation of vinyl iodide 115 to give 116 (Scheme 20).28e Enhanced conversions were attained using copper(i) thiophenecarboxylate (GuTG) in a polar aprotic solvent such as NMP. The total synthesis of the antitumor natural product, lobatamide G, has been accomplished by using this reaction.28f Buchwald et al. developed a general and efficient copper-catalyzed method using N,N -dimethyl ethylenediamine L8. The double-bond geometry of the alkenyl halides was retained under the reaction conditions. 

---