Ethylene glycol complexes

The hydrodynamic behavior of complex particles in solution is similar to that of suspensions of solid spheres. Applying to the solutions of the PMAA-poly(ethylene glycol) complex, Einstein s equation for the viscosity of suspension of spherical particles, t]Sp/c = 2.54 q> (where tp is the volume fraction of dissolved substance) the solvent content in complex coils has been estimated33. It is about 75 vol%, i.e. the complex particles contain comparatively small quantities of the solvent in comparison with a usual random coil in solution which contains about 97-99 vol% of solvent34. ... 

Liu, G., Ding, X., Cao, Y., Zheng, Z., and Peng, Y. 2004. Shape memory of hydro-gen-bonded polymer network/poly(ethylene glycol) complexes. Macromolecules 37 2228-2232. 

Ge, L., X. Zhang, and R. Guo (2007). Microstructure of Triton X-100/poly(ethylene glycol) complex investigated by fluorescence resonance energy transfer. Polymer 4S(9) 2681-2691. 

Polymerization of phenylalanine catalyzed by a-chymotry in-poly(ethylene glycol) complex was examined [48]. The solvent used is chloroform saturated by Tris buffer (pH 7). The monomer conversion was 72% giving the dimer and then the hexamer. 

The IR spectra of PEO in the liquid state or in solution may be interpreted by comparing them with the assigned bands in the vibrational spectra of crystalline PEO [20, 26, 27] and structurally related compounds such as 1,2-dichlorethane, [19, 21-23]. ethylene chlorohydrin [30], metal-ethylenediamine complexes [31, 32] ester and ether derivative of ethylene glycol [33], crystalline polyesters [34], and metal-ethylene glycol complexes [35]. 

Actinide ions form complex ions with a large number of organic substances (12). Their extractabiUty by these substances varies from element to element and depends markedly on oxidation state. A number of important separation procedures are based on this property. Solvents that behave in this way are thbutyl phosphate, diethyl ether [60-29-7J, ketones such as diisopropyl ketone [565-80-5] or methyl isobutyl ketone [108-10-17, and several glycol ether type solvents such as diethyl CeUosolve [629-14-1] (ethylene glycol diethyl ether) or dibutyl Carbitol [112-73-2] (diethylene glycol dibutyl ether). 

A provocative reaction of ethylene glycol direcdy with siUcon dioxide that leads to a complex mixture of oligomeric and cycHc ester species has been reported (32). This reaction proceeds in the presence of sodium hydroxide or in the presence of high boiling tertiary amines (33). 

The addition product, C QHgNa, called naphthalenesodium or sodium naphthalene complex, may be regarded as a resonance hybrid. The ether is more than just a solvent that promotes the reaction. StabiUty of the complex depends on the presence of the ether, and sodium can be Hberated by evaporating the ether or by dilution using an indifferent solvent, such as ethyl ether. A number of ether-type solvents are effective in complex preparation, such as methyl ethyl ether, ethylene glycol dimethyl ether, dioxane, and THF. Trimethyl amine also promotes complex formation. This reaction proceeds with all alkah metals. Other aromatic compounds, eg, diphenyl, anthracene, and phenanthrene, also form sodium complexes (16,20). 

The addition of one mole of a diol, such as ethylene glycol, 1,2-propanediol, or 1,4-butanediol, to bis-acetylacetone titanate complexes gives a complex that is stable on dilution with water and that can be used in aqueous printing inks (509). An excellent review of the use of organic titanates in printing inks is available (510). 

Complex nitrogen compounds are formed from the reaction of aLkylamines with ethylene oxide (61). Thus diethylamine and ethylene oxide react to yield diethylaminoethanol. The diaLkylarninoethanols can react with ethylene oxide to give amino poly(ethylene glycols) ... 

Example. The Pechini method for fuel cell electrode preparation. La, Ba, Mn niU ates - - CgHgO — citrate complex - - C2FI6O2 — gel. Metal nitrates are complexed with citric acid, and then heated with ethylene glycol to form a transparent gel. This is then heated to 600 K to decompose the organic content and then to temperatures between 1000 and 1300K to produce tire oxide powder. The oxide materials prepared from the liquid metal-organic procedures usually have a more uniform particle size, and under the best circumstances, this can be less than one micron. Hence these particles are much more easily sintered at lower temperatures than for the powders produced by tire other methods. 

The 12-ketone is generally less reactive than 3-, 6- and 7-ketones but more reactive than the 11-ketone. 12-Ethylene ketals are readily prepared by the usual procedures and the 12-ketone can be selectively ketalized in the presence of a 20-ketone bearing a 17a-hydrogen or 17a-hydroxyl substituent [(81)- (82)]. ° The procedure of choice for this reaction utihzes ethylene glycol and boron trifluoride-ether complex at room temperature. 

A slightly more complex anti arrhythmic agent is pi rmentol (74). It is synthesized from 4-chloropropiophenone (72) by keto group protection as the dioxolane (with ethylene glycol and acid) followed by sodium iodide-mediated alkylation with cis 2,6-dimethyl pi peri dine to give 7. Deblocking with acid followed by addition of 2-1ithiopyridine completes the synthesis of pi rmentol (74). 

Replacement of silver nitrite by inexpensive sodiiunor potassium nitrite enhances the imlity of this process Treatment of alkenes v/ith sodiiun nitrite and iodine in ethyl acetate and water in the presence of ethylene glycol gives conjngatednitroalkenesin49-82% yield The method for generation of nitryl iodide is improved by the treatment of iodme v/ith potassium nitrite complexed v/ith 18-crovm-6 in THF under sonicadon, as shovmin Eq 2 32 ... 

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