Acetic acid, glacial properties

Physical properties. All are colourless crystalline solids except formic acid, acetic acid (m.p. 18 when glacial) and lactic acid (m.p. 18°, usually a syrup). Formic acid (b.p. loo ") and acetic acid (b.p. 118 ) are the only members which are readily volatile lactic acid can be distilled only under reduced pressure. Formic and acetic acids have characteristic pungent odours cinnamic acid has a faint, pleasant and characteristic odour. 

Theophrastos (272—287 Bc) studied the utilisation of acetic acid to make white lead and verdigris [52503-64-7]. Acetic acid was also weU-known to alchemists of the Renaissance. Andreas Libavius (ad 1540—1600) distinguished the properties of vinegar from those of icelike (glacial) acetic acid obtained by dry distillation of copper acetate or similar heavy metal acetates. Numerous attempts to prepare glacial acetic acid by distillation of vinegar proved to be in vain, however. 

A summary of the physical properties of glacial acetic acid is given in Table 5. ... 

Chlorides. The oHve-green trichloride [10025-93-1], UCl, has been synthesized by chlorination of UH [13598-56-6] with HCl. This reaction is driven by the formation of gaseous H2 as a reaction by-product. The stmcture of the trichloride has been deterrnined and the central uranium atom possesses a riine-coordinate tricapped trigonal prismatic coordination geometry. The solubiUty properties of UCl are as follows soluble in H2O, methanol, glacial acetic acid insoluble in ethers. 

The phenethylamine homologue of TMA-6 is well known, but is virtually unexplored pharmacologically. The above benzaldehyde with nitromethane in glacial acetic acid containing ammonium acetate gave the appropriate beta-nitrostyrene as yellow crystals with a mp 177-177.5 °C. This, with LAH in ether, gave 2,4,6-trimethoxyphenethylamine (2,4,6-TMPEA, or 2C-TMA-6) as the picrate salt (mp 204-205 °C) or the hydrochloride salt (mp 234-235 °C). It has been shown not to be a substrate to the soluble amine oxidase from rabbit liver, a property it shares with mescaline, but whether it is or is not active in man is at present unknown. 

Tandon and Chhor reported 3,4-diphenyl-3,4-dihydro[l,2]-diazete-l,2-dioxide 95 by the oxidation of diazete with hydrogen peroxide in glacial acetic acid <2004LOC40>. These authors wanted to investigate NO donor properties of these iV]./V-dioxides. The A,iV-dioxides can undergo thermal exclusion of NO to furnish diphenylacetylene 96 (Equation 15). 

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