2- ethanediol

Colorless viscous liquid with a weak coconut oil odor bp 155-175°C (311-347°F) density 0.919-0.945 solnble in alcohol and ether. 

Methylcyclohexanol is mildly toxic. Inhalation may produce mild irritation of the eyes and the respiratory system, and headache. Studies in rabbits showed that this compound could cause rapid narcosis and convulsion at sublethal doses. The minimum lethal dose by oral administration was 2000 mg/kg. Severe exposure may produce narcosis in humans. Skin absorption may canse dermatitis. 

The air is sampled over charcoal and desorbed by methylene chloride, and the eluant is analyzed by GC-FID. 

Structure HO—CH2—CH2—OH Synonyms ethylene glycol 1,2-dihydroxy-ethane ethylene dihydrate ethane-1,2-diol 

Ethylene glycol is used as an antifreeze in heating and cooling systems (e.g., automobile radiators and coolant for airplane motors). It is also used in the hydraulic brake fluids as a solvent for paints, plastics, and inks as 

ENICHEM, HOUGHTON, SHELL, UNION CARBIDE 

Inhalation of 1,2-ethanediol causes respiratory tract irritation. 

Ecotoxicity 1,2-Ethanediol is known to be relatively non-persistant (aerobic biodegradation half-lives ranging from 2 to 18 days), and to dispose of low aquatic toxicity. 

The suggestion that 1,2-ethanediol because of its low loc octanol/water partition coefficient does not accumulate to significant levels in the tissues of aquatic biota, is corroborated by long term studies with crayfish (Kent et al., 1999). 

2- Ethanediol does not exhibit substantial antimicrobial activity. However, due to its hygroscopic (water binding) properties it may affect microbial proliferation, e.g. in cosmetics and toiletries, by reducing the available water in the corresponding formulations. Also remarkable is the fact that the addition of formaldehyde (2.1.) to 

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Diols that bear two hydroxyl groups m a 1 2 or 1 3 relationship to each other yield cyclic acetals on reaction with either aldehydes or ketones The five membered cyclic acetals derived from ethylene glycol (12 ethanediol) are the most commonly encoun tered examples Often the position of equilibrium is made more favorable by removing the water formed m the reaction by azeotropic distillation with benzene or toluene... 

The last variation we should discuss is about the use of solvent. Ever-bitching about the rarity and price of chemicals, the bees have thrust their anger at the DMF used in this method. TDK sent Strike an article that gives some credence to this [16]. In it the alcohols methanol, ethanol, 1-propanol, ethanediol and others were used in place of DMF with beautifully high yields. Below is the sample experimental from the article Oust picture using safrole or allylbenzene in place of the 1-hexene) ... 

The most commonly used protected derivatives of aldehydes and ketones are 1,3-dioxolanes and 1,3-oxathiolanes. They are obtained from the carbonyl compounds and 1,2-ethanediol or 2-mercaptoethanol, respectively, in aprotic solvents and in the presence of catalysts, e.g. BF, (L.F. Fieser, 1954 G.E. Wilson, Jr., 1968), and water scavengers, e.g. orthoesters (P. Doyle. 1965). Acid-catalyzed exchange dioxolanation with dioxolanes of low boiling ketones, e.g. acetone, which are distilled during the reaction, can also be applied (H. J. Dauben, Jr., 1954). Selective monoketalization of diketones is often used with good success (C. Mercier, 1973). Even from diketones with two keto groups of very similar reactivity monoketals may be obtained by repeated acid-catalyzed equilibration (W.S. Johnson, 1962 A.G. Hortmann, 1969). Most aldehydes are easily converted into acetals. The ketalization of ketones is more difficult for sterical reasons and often requires long reaction times at elevated temperatures. a, -Unsaturated ketones react more slowly than saturated ketones. 2-Mercaptoethanol is more reactive than 1,2-ethanediol (J. Romo, 1951 C. Djerassi, 1952 G.E. Wilson, Jr., 1968). 

Recently, Koitai et al. (17) have shown that 5,5-diphenyl-2,4-thiazolidinedithione (15) with aluminum chloride in refluxing toluene gives 4,5-diphenyl-A-4-thia2oline-2-thione (16) (Scheme 7). 3-Methyl-4,5-diphenyl (17) and 4,5-diphenyl-A-4-thia2oline-2-thiones (16) are obtained in very low yields (1 to 5%) as by-products of the reaction between deoxybenzoin. benzoin. l,2-diphenyl-1.2-ethanediol. 1.2-diphenylethanol, or benzil, and Sg in hexamethylphosphoamide (18), The transformation of A-4-thiazoline-2-ones to the corresponding thiones by P2S5 (19) is of little synthetic value since the latter are more easily prepared. 

Vicinal diols are diols that have their hydroxyl groups on adjacent carbons Two commonly encountered vicinal diols are 1 2 ethanediol and 1 2 propanediol... 

Construct molecular models of the gauche and anti conformations of 1 2 ethanediol and explore the possibility of intramolecular hydrogen bond formation in each one... 

A large number of a-hydroxybenzylbenzimidazole [50-97-5] (HBB, 39), C24H22N2O, derivatives has been prepared and extensively studied as selective inhibitors of the RNA containing enterovimses (91). Although none of these derivatives have shown any antiviral activity in animals, l,2-bis(5-methoxy-2-benzimidazol-2-yl)-l,2-ethanediol [16656-27-2] (40), C2gH2gN404, was found to be active against an experimentally induced rhino vims infection in chimpanzees (92). However, the in vivo antiviral efficacy was accompanied by significant toxicity. 

Oxirane is used as a fumigant for grain and a sterilant e.g. for space vehicles bound for putative abodes of life), but mainly for the manufacture of 1,2-ethanediol ( ethylene glycol ), emulsifiers, plastics and resins (below), plasticizers, synthetic rubber and synthetic fibers. Methyloxirane is used mainly to make detergents, hydraulic fiuids and lubricants. 

Ethylene glycol 1,2-Ethanediol 95 CoHeOo 1,2-Propylene glycol 1,2-Propanediol 96 C,HsOj... 

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