Tris alcohols

Solvates of the monohydroxylic alcohols have been extensively studied. The expected pattern of more solvent molecules per chloride molecule is reported for the lanthanide and yttrium trichlorides. For scandium trichloride, the existence of ScCl3-2EtOH and ScCl3-2C6H13OH compares unexpectedly with the tris-alcoholates reported for the n-C6... 

Up to 1890, hydroxylamine was known only in the form of its salts or in aq. soln. W. Lossen tried, without success, to isolate the base by distilling the aq. soln. C. A. Lobry de Bruyn assumed that the presence of water was the secret of W. Lossen s failure to isolate the base, and he tried alcohol as solvent. Solubility of the hydroxylamine in methyl alcohol was found to be greater than in ethyl alcohol. He succeeded in isolating the base by distillation from a mixture of sodium methoxide, and hydroxylamine chloride. 

In equation 1, a dicarboxylic acid derivative called an anhydride (literally without water ) reacts with ethylene glycol, a di-alcohol, to form a linear polyester and the byproduct water. Ethylene glycol is the major ingredient in most automotive radiator fluids. In equation 2, the ethylene glycol is replaced with a tri-alcohol, glycerol. As the reaction proceeds, the polyester does not form linear chains, but rather becomes crosslinked as the three OH groups react with phthalic anhydride, building up a three-dimensional structure. 

Literature covering the composition and structure of lanthanide complexes in nonaqueous media is not extensive [128,219]. Anhydrous LnCL in alcohol yielded crystalline tris-alcoholates. These compounds gave intense bands due to 3H4 3P2 transition in... 

Fats and oils are esters of glycerol, the simplest triol (tri-alcohol), in which each of the three hydroxyl groups has been converted to an ester. The acid portion of the ester linkage (fatty acids) usually contains an even number of carbon atoms in an unbranched chain of 12 to 24 carbon atoms. The triesters of glycerol fats and oils are also known as triglycerides. 

With 2,4-substituted, bispidones of lower symmetry and analoguous 1,5-dicarboxylic acid esters (e.g., compounds 10-48 in Table 1) the reduction under Wolff-Kishner conditions fails, but reaction with complex hydrides leads to the corresponding bispidoles. The treatment with LiAUTj yields a 1 1 mixture of the epimeric tris alcohols, whereas reduction with NaBELj at ambient temperature in various solvents leads to the epimeric mono-alcohols in different ratios up to epimerically pure compounds (see Scheme 9) (116, 117), which can be further reduced to the tris alcohols with LiAlH4. For example, the reduction of 14 with NaBH4 in dry methanol yields 65% syn- (84b) and 35% anri-product (84a), while the reaction in a mixture of dioxane-water leads exclusively to the anti-configuration of alcohol 84a (117). 

As stated in Section 2.4, the condensation reaction may be the basis for the mechanism of stepwise polymerization. As long as the functionality equals 2 (di-acid and di-alcohol in polyester or di-amine in polyamide), only linear chains are obtained. However, once polyfunctionality prevails (appearance of tri-alcohol like glycerol, or tri-acid), reactive branches are formed that may interact and lead to a three-dimensional structure, called cross-linked (gelation). This is the basis for thermosetting polymers on one hand, or for stabilizing the elastomeric chain on the other hand (replacing vulcanization). 

Figure 11.34 Esterification of the tri-alcohol glycerol yields a triglyceride. A saturated fat is maximally "saturated" with hydrogen and has no C=C reactive sites. Saturated triglycerides are waxy solids while unsaturated triglycerides tend to be liquid oils. 

Soy oil-based polyols were prepared by catalytic ozonation in the presence of various di- and tri-alcohols. An example of this reaction with ethylene glycol is shown in Figure 12. Here, the double bonds are cleaved and the new chain-ends react with one hydroxyl group of the ethylene oxide leaving the other hydroxyl as a new, primary hydroxyl chain-end. As described in the previous... 

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