Propionic acid hydrate

The pure dimethylaminoethanol salt was dissolved in 400 ml of 50% acetic acid at 90°C and then cooled to 5°C. The solid which precipitated was collected by filtration, washed with water, cold 50% acetic acid and finally with low-boiling petroleum ether. After drying in vacuo there was obtained 24 g of hydrated dextro-/3-(3,5-diiodo-4-hydroxy)-a-phenyl-propionic acid, MP 80° to 85°C. 

Coumarin (7.88) is a well-known 6-lactone (six-membered ring) of natural origin found in various preparations such as some tobaccos, alcoholic beverages, and cosmetics. Besides reactions of oxidation, reduction, and conjugation, coumarin is also subject to lactone hydration in vivo and in the presence of microsomes [170-174], The resulting metabolites include ortho-coumaric acid (7.89) formed directly from coumarin, 3-(2-hydroxyphenyl)-propionic acid (7.91) formed following reduction of coumarin to dihydrocou-... 

Horse radish peroxidase on the other hand, is a hemoprotein which is inhibited by alkylation of the porphyrin ring 48 by a -propionic acid radical resulting from the ring cleavage of the cyclopropanone hydrate 21, providing the car-boxylate 49,Eq. (17). 

Ibuprofen (+) -2- (4-Isobutylphenyl) propionic acid Aromatic alkylation, HF-catalyzed aromatic acetylation, palladium-catlayzed carbonylation, alkene hydration... 

Other than water, protein is the major constituent of meat averaging nearly 21% in heef or chicken meat, with fat varying fiom 4.6 to 11.0% in beef and fiom 2.7 to 12.6% in chickoi. The principal radiolytic reactions of aqueous solutions of aliphatic amino acids are reductive deamination and decarboxylation. Alanine yields NH3, pyruvic add, acetaldehyde, propionic acid, CO2, H2, and ethylamine (6). Sulfur-containing amino adds are espedally sensitive to ionizing radiation. Cysteine can be oxidized to cystine by the hydroxyl radical or it can react with the hydrated electron and produce... 

Reaction of 2-aminopyridines with acrylic acid or methacrylic acid in boiling water for 2-20 hours gave betaine hydrates 262 (R3 = H) in 11-88% yields (Scheme 20) (92KGS80). When 2-aminopyridine reacted with methyl metharylate in acetic acid for 24 hours or 2-aminopyridine and its 5-bromo and 5-chloro derivatives reacted with acrylic acid in boiling toluene for 24 hours or 2-aminopyridine reacted with crotonic acid in boiling toluene for 20 hours, 3-(2-pyridylamino)propionic acid derivatives 263 were the products. When 5-chloro-2-aminopyridine reacted with acrylic... 

The hydrate and hemiacetals of cyclopropanone are rapidly formed in good yields by the addition of water and alcohol, respectively, to a solution of the ketone. 1-8>io) These derivatives may be isolated and purified, but they tend to rearrange to propionic acids or esters when stored at room temperature (Scheme 13). 

Propenoic acid is commonly known as acrylic acid (p. 172), and j(3-hydroxy propionic acid is therefore named hydracrylic acid, i.e., hydrated acrylic acid. 

Here the relationship is that of loss or addition of water, the name hydr-acrylic meaning hydrated acrylic, whereas the relationship between ciimamic acid and hydrociimamic is loss or addition of hydrogen, the name hydro-cinnamic meaning hydrogenated cinnamic. The same relationship is expressed in the case of propionic acid if we name it hydro-acrylic acid. 

Hydrate on Methane and Propionic Acid in the Rumen, Appl Microbiol (1969) 17, 695-700. 

In addition, the presence of hydrogen opens up the way to various possible side reactions such as the formation of ethane by hydrogenation of ethylene or the formation of diethyl ketone from ethylene, carbon monoxide, and hydrogen. Ethanol is formed independently by hydration of ethylene, which condenses with propionic acid to form the corresponding ester. 

Rochelle (7) evaluated available kinetic data on sulfite addition to maleic or acrylic acid to give sulfosuccinic or 8-sulfopropicnfc acid. Cavanaugh (14) demonstrated the feasibility of hydrating acrylic acid with H2SO4 catalysis at 100°C to get g-hydroxy-propionic acid. 

Cellulose acetate is the most well known plastic with a cellulose base. Others are cellulose acetobutyrate and cellulose propionate. Cellulose hydrate may be used as a vulcanized fiber. Cellulose may be identified fairly simply. Dissolve or suspend a sample in acetone, react it with 2-3 drops of a 2 % solution of a-naphthol in ethanol, and carefully introduce a layer of concentrated sulfuric acid under this. At the phase boundary, a red to red-brown ring forms. In the presence of cellulose nitrate, a green ring forms. Sugars and lignin produce interference. For differentiation between cellulose acetate and cellulose acetobutyrate, it is usually sufficient to examine the vapors produced by dry heating of the sample. The acetate smells like acetic acid the acetobutyrate smells of both acetic acid and butyric acid (like rancid butter). 

Another effect is observed in the case of propionate acids and their sodium salts. At low concentration the hydration is accelerated but at high-retarded. The complexes with Ca ions are formed thus increasing the calcium ions concentration in the solution. This accelerates the decomposition of primary hydrate. At higher concentration the organic anions are adsorbed on the surface of CjS and the calcium propionate is formed. By hampering the hydration process, a-hydroxy acids (for example lactic acid) and their salts have a veiy strong delaying effect. This is the... 

Zych and Drozdzyhski (1991) synthesized AjUBrg, A = K, Rb, from UBr dissolved in methylcyanide with a large excess of the group 1 bromide. The mixture was acidified with propionic acid and the U(IV) reduced with zinc amalgam. The precipitate which formed upon reduction, a methyl cyanide-hydrate, could be decomposed thermally in high vacuum to yield the anhydrous compounds structural data were not presented. Solid-state absorption spectra taken from thin films and magnetic-susceptibility measurements are consistent with the presence of an cation. The authors indicate that... 

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