Benzoic acid benzoin

RP-8, F254 Acetonitrile / HP (6/4) UV 254 nm Benzoic acid. Benzoin, Ethyl benzoate 29... 

Benzoic acid/benzoin tincture Methyl salicylate... 

Aniline hydrochloride Antimony trioxide Benzoic acid Benzoin IH-Benzotriazole... 

Dumas, working with the French apothecary Pierre Francois Guillaume Boullay, first proposed that the ethylene group (a two-carbon chain) could serve as the radical base for alcohol and related compounds. The concept of radicals received further support when Liebig and Wohler published their work on oil of bitter almonds. They found a family of compounds— benzoic acid, benzoin, benzaldehyde, benzoyl chloride, benzoyl bromide, benzoyl iodide, benzoyl cyanide, benzoyl... 

It was first described in 1608 when it was sublimed out of gum benzoin. It also occurs in many other natural resins. Benzoic acid is manufactured by the air oxidation of toluene in the liquid phase at 150°C and 4-6 atm. in the presence of a cobalt catalyst by the partial decarboxylation of phthalic anhydride in either the liquid or vapour phase in the presence of water by the hydrolysis of benzotrichloride (from the chlorination of toluene) in the presence of zinc chloride at 100°C. 

Benzoic acid had been known for several hundred years by the time of Mitscher lich s experiment Many trees exude resinous materials called balsams when cuts are made m their bark Some of these balsams are very fragrant which once made them highly prized articles of commerce especially when the trees that produced them could be found only m exotic faraway lands Gum benzoin is a balsam obtained from a tree that grows m Java and Sumatra Benzoin is a word derived from the Erench equivalent benjoin which in turn comes from the Arabic luban jawi meaning incense from Java Benzoic acid is itself odorless but can easily be isolated from gum benzoin... 

Benzoic acid [65-85-0] C H COOH, the simplest member of the aromatic carboxyHc acid family, was first described in 1618 by a French physician, but it was not until 1832 that its stmcture was deterrnined by Wn b1er and Liebig. In the nineteenth century benzoic acid was used extensively as a medicinal substance and was prepared from gum benzoin. Benzoic acid was first produced synthetically by the hydrolysis of benzotrichloride. Various other processes such as the nitric acid oxidation of toluene were used until the 1930s when the decarboxylation of phthaUc acid became the dominant commercial process. During World War II in Germany the batchwise Hquid-phase air oxidation of toluene became an important process. 

Benzoic acid in the free state, or in the form of simple derivatives such as salts, esters, and amides, is widely distributed in nature. Gum benzoin (from styrax ben in) may contain as much as 20% benzoic acid in the free state or in combinations easily broken up by heating. Acaroid resin (from anthorrhoca haslilis) contains from 4.5 to 7%. Smaller amounts of the free acid are found in natural products including the scent glands of the beaver, the bark of the black cherry tree, cranberries, pmnes, ripe cloves, and oil of anise seed. Pern and Tolu balsams contain benzyl benzoate the latter contains free benzoic acid as well. The urine of herbivorous animals contains a small proportion of the glycine derivative of benzoic acid, hippuric acid [495-69-2] (CgH CONHCH2COOH). So-called natural benzoic acid is not known to be available as an item of commerce. 

Mohler has just shown that copper, pyridine and air oxidize benzoin to benzoic acid. Also, the same oxidation takes place in the absence of copper. 

Benzoe resin (also known as benzoin) comes from Styrax spp. (Styraceae family). In the Sty rax genus the only species that occurs in the Mediterranean is Styrax officinalis, so this was probably the source of the resin in ancient times in that area. Benzoe mainly contains free cinnamic and benzoic acids, and their corresponding esters with cinnamyl, p-coumaryl and coniferyl alcohols. The amounts of these compounds are quite variable and depend on which species the resin was obtained from [129]. 

From this point of view, a brief comparison of acyloxylation of cis- or irany-stilbenes in electrochemical and chemical conditions is also relevant. Oxidation of cis- or irany-stilbene at the platinum anode in the presence of acetic or benzoic acid gives predominantly meyo-diacylates of hydroxy-benzoin or, if some water is present, t/treo-monoacylate. None of the stereoisomeric erythro-mono-acylate and rac-diacylate were obtained in either case. There was no evidence of isomerization of cis- to trany-stilbene nnder the electrolytic conditions employed (Mango and Bonner 1964, Koyama et al. 1969). The sequence of reaction steps in Scheme 2.27 was proposed. Adsorption-controlled one-electron oxidation of the snbstrate takes place. Then the cis-stilbene cation-radical interact with acetate to form an oxonium ion. The phenyl groups in the oxoninm adopt the trans mntnal disposition which is thermodynamically preferential. The trany-benzoxoninm ion is the common intermediate for conversions of both cis- and trany-stilbenes and, of conrse, for all the final prodncts (Scheme... 

Recently a complete product study has been carried out for benzil irradiated in cyclohexane.63 A complex mixture containing benzaldehyde, phenyl-cyclohexyl ketone, benzoin benzoate, benzoin, benzoic acid, and smaller amounts of other compounds containing from three to six benzyl groups was obtained. 

N.A. Styrax benzoin Dryander Cinnamic, benzoic, sumaresinolic acid esters, benzoic acid, benzaldehyde, vanillin.99 Antiseptic, astringent. Externally for wounds and ulcers, internally to settle cramps, stimulate coughing, disinfect the urinary tract. 

Benzoic acid, 706,711, 752,755,756 Benzoic anhydride, 794 Benzoin, 708,714 Benzoin condensation, 708, 714 a-Benzoin oxime, 958 Benzonitrile, 609, 803 hydrolysis of, 609 ... 

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