Propane-1,2,3-triol, glycerol

Benzanthrone (6.73) is the source of various commercially important violet, blue and green vat dyes. This tetracyclic system can be prepared from a mixture of anthraquinone and propane-1,2,3-triol (glycerol) by heating with iron powder in concentrated sulphuric acid. The reaction involves reduction of anthraquinone to anthrone (6.74) followed by condensation (Scheme 6.14) with propenal (acrolein), the latter compound being generated... 

Increasing the number of hydroxy groups in the substrate results in a sharp decrease in the yield of fluorinated compounds due to resinification and carbonization. This may be avoided by conducting the reactions at low temperatures in anhydrous hydrogen fluoride. Thus, the reaction of sulfur tetrafluoride with propane-1.2,3-triol (glycerol) at — 40 C gives 3-fluoro-propane-l,2-diyl sulfite (5) in high yield.60... 

Fats are natural esters of propane-1,2,3-triol (glycerol). Soap used to be made by boiling animal fats with alkali this is why the hydrolysis of esters used to be called saponification . 

Common alcohols are used as solvents, denaturing agents, chemical feedstocks, and in antifreeze preparations. Ethanol is the intoxicating ingredient in alcoholic beverages. Propane-1,2,3,-triol (glycerol) is used to make polymers, cosmetic emollients, and sweeteners. 

The reaction of KMn04 with propan-1,2,3-triol (glycerol). 

Thermosetting space-network polymers can be prepared through the reaction of polybasic acid anhydrides with polyhydric alcohols. A linear polymer is obtained with a bifunctional anhydride and a bifunctional alcohol, but if either reactant has three or more reactive sites, then formation of a three-dimensional polymer is possible. For example, 2 moles of 1,2,3-propane-triol (glycerol) can react with 3 moles of 1,2-benzenedicarboxylic anhydride (phthalic anhydride) to give a highly cross-linked resin, which usually is called a glyptal ... 

The oils that are of particular interest to the paint chemist are the fatty oils, which are largely vegetable oils pressed or extracted from the seeds or fruit of many types of vegetable matter. These are esters of 1,2,3-propane triol (glycerol), in which all three hydroxyl groups are reacted with fatty acids. The majority of these acids contain 18 carbon atoms. The triple esters are normally referred to as triglycerides. 

Glycerin palmitostearate glycerol palmitostearate 2-[(l-oxo-hexadecyl)-oxy]-l,3-propanediyl dioctadecanoate and 1,2,3-propane triol Precirol ATO 5. 

These are naturally occurring esters of the triol glycerol (propan-1,2,3-triol). A fat is a substance that is solid at room temperature, whereas an oil is liquid. In vegetable oils, the hydrocarbon chains have many double bonds (they are polyunsaturated). Fats, however, tend to have very few, or no double bonds. Removal of most of the double bonds in a vegetable oil, by reaction with hydrogen (hardening), will convert it to a solid fat. Hardened corn oil, for example, is used to make margarine. 

CH2OH.CH2OH ethane-1,2-diol (ethylene glycol) - used in antifreeze CH2OH CHOH CH2OH 1,2,3-propane-triol (glycerine or glycerol)... 

The saponification of fats, which are esters of propane-l,2,3-triol (glycerol) with long-chain carboxylic acids, forms soaps. 

The majority of fatty acids in tissues are combined with other molecules. In food fats and oils, fatty acids are esterified to molecules of glycerol (propane-1,2,3-triol). Figure 11.3 shows how three fatty acids can combine with a single... 

The commonest approach is the Skraup synthesis. Here a mixture of glycerol (propane-1,2,3-triol), aniline (phenylamine), sulfuric acid, nitrobenzene and ferrous [iron(II)] sulfate are heated together (Scheme... 

Glycerol (propane-1,2,3-triol) is a very important structural part of the phospholipids, the major components of natural membrane bilayers. Based on this natural scaffold, diesters of glycerol and of related derivatives have been extensively used for the construction of synthetic building blocks carrying vicinal lipid chains (for examples, see Scheme 14). 

Glycerol (propan-1,2,3-triol) is a readily available raw material from biosus-tainable sources such as rape-seed and sunflower the many products that can be formed from it by oxidation find economic use as intermediates in the fine chemicals industry. However, its oxidation constitutes a complicated scenario by reason of the parallel and sequential reaction paths that can be followed (Scheme 8.3) obtaining a desired product therefore constitutes a considerable challenge. The mono-aldehyde readily isomerises under basic conditions to dihydroxyacetone, but fortunately it is less easily oxidised, so that glyceric acid (HOCH2-CH(OH)-CC>2H) is frequently a major product. Gold catalysts, as in other reactions, do not suffer from deactivation, nor do... 

Glycerol (propane-1,2,3-triol) is a viscous symp with molecular weight 92 g/mol, boiling point 290 °C, and density... 

The most common types of lipids are esters of glycerol. Glycerol is just propane-1,2,3-triol but it has interesting stereochemistry. It is not chiral as it has a plane of symmetry, but the two primary Oh[ groups are enantiotopic (Chapter 16), If one of them is changed—hy esterification, for example—the molecule becomes chiral. Natural glycerol phosphate is such an ester and it is optically active. 

Simple trihydric alcohols contain three OH groups per molecule and an example is propan-1,2,3-triol or glycerol or glycerine (Figure 3.3). Its derivatives and compounds figure greatly in the structures of fats (lipids see Section 4.8). 

Some pharmacopeias also contain specifications for diluted glycerin solutions. The JP 2001 contains a monograph for glycerin that contains 84-87% of propane-1,2,3-triol (C3H8O3). The PhEur 2005 contains a monograph for glycerol 85 per cent that contains 83.5-88.5% of propane-1,2,3-triol... 

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