Hydroxy acetic acid

The next higher hydroxy acid is hydroxy acetic acid CH2(OH)— COOH, known also as glycolic acid. It may be prepared (a) from chlor acetic acid, (b) from the cyan-hydrine obtained from formic aldehyde, or (c) hy the oxidation of ethylene glycol, by reactions which have been already discussed. Its relation to ethylene glycol gives it the name of glycolic acid. It may be considered as a direct oxidation product of ethane. 

Glycolic acid is a crystalline solid melting at 7g°-8o°, and is easily soluble in water. It forms an anhydride, ethers and esters as has been explained for hydroxy acids in general. As there are only two carbon atoms present no other hydroxy acetic acid is possible. The double anhydride of glycolic acid is known as glycolide and is obtained when 

Both are obtained from two molecules of glycolic acid by the loss of two molecules of water. In di-glycolic acid anhydride one molecule of water is formed from the two alcohol hydroxyls and one from the two acid hydroxyls. In glycolide each molecule of water is formed from one alcohol hydroxyl and one acid hydroxyl. The first is an anhydride of an ether-acid, di-glycolic acid, while glycolide is a double ester of an alcohol-acid. 

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Cyclopentyl- 3-(N-piperidyl)ethyl ketone Cycrimlne HCI /3-Cyclopentyl propionic acid Testosterone 17/3-cypionate Cyclopentyl (tt-thienyl) hydroxy acetic acid Penthienate bromide Cyclopropanecarboxylic acid chloride Prazepam... 

Lieb, F., Oediger, H., and Streible, G., Phosphono-Hydroxy-Acetic Acid and Its Salts, Their Production and Their Medicinal Use, U.S. Patent 4,340,599, 1982. 

Alkyl- or 3-aryl-2,4-oxazolidinediones via photochemical cyclization, ° organonickel-mediated carbonylation, ° cyclization of A-alkenyl-a-acet-amides, ° carboxylation and cyclization of 2-propynamides, °" cyclization of (9-carbamates of a-hydroxy acetic acids and esters,cyclization of a-hydroxy acetamides,and catalytic asymmetric dihydroxylation (ADH) of A-alkenoyl-2-oxazolidinones. ... 

One Sanofi synthesis of enantiomerically pure (-i-)-clopidogrel (2) utilized optically pure (R)-(2-chloro-phenyl)-hydroxy-acetic acid (20), a mandelic acid derivative, available from a chiral pool. After formation of methyl ester 21, tosylation of (/ )-21 using toluene sulfonyl chloride led to a-tolenesulfonate ester 22. Subsequently, the Sn2 displacement of 22 with thieno[3,2-c]pyridine (8) then constructed (-i-)-clopidogrel (2). Another Sanofi synthesis of enantiomerically pure (-i-)-clopidogrel (2) took advantage of resolution of racemic a-amino acid 23 to access (S)-23. The methyl ester 24 was prepared by treatment of (S)-23 with thionyl chloride and methanol. Subsequent Sn2 displacement of (2-thienyl)-ethyl para-toluene-sulfonate (25) assembled amine 26. 

Hydroxy-acetic acid (glycolic acid). HOCH-COOH. is the first and simplest member of the family of hydroxycarboxylic acids. It occurs naturally as the chief acidic constituent of sugar-cane juice and also occurs in sugar beets and unripe grape juice. It is widely used as a cleaning agent for a variety of industrial applications, and also as a specialty chemical and biodegradable copolymer feedstock. 

Lee S-H, Mendenhall GD (1988) Relative yields of excited ketones from self-reactions of alkoxyl and alkylperoxyl radical pairs. J Am Chem Soc 110 4318-4323 Leitzke A, Reisz E, Flyunt R, von Sonntag C (2001) The reaction of ozone with cinnamic acids - formation and decay of 2-hydroperoxy-2-hydroxy-acetic acid. J Chem Soc Perkin Trans 2 793-797 Lodhi ZH, Walker RW (1991) Oxidation of allyl radicals kinetic parameters for the reactions of allyl radicals with H02 and 02 between 400 and 480 °C. J Chem Soc Faraday Trans 87 2361-2365 Martini M, Termini J (1997) Peroxy radical oxidation of thymidine. Chem Res Toxicol 10 234-241... 

When treated with sodium hydroxide dissolved in THE the product of Step 1 was converted into 2-propyl-cr-hydroxy-acetic acid as is illustrated in Eq. 2 ... 

ANEDCO AC-163 is a versatile basic intermediate which can be further modified by reacting with dimer-trimer acids to obtain an excellent film persistent-corrosion inhibitor. Various surfactants may be added to obtain improved water dispersibility. ANEDCO AC-163 may be reacted with a short chain organic acid such as acetic acid, hydroxy acetic acid, etc. to form a water-soluble corrosion inhibitor. 

Ethyl ether of hydroxy acetic acid ester... 

Di-(hydroxy acetic acid) ether Di-glycolic acid... 

The ether which is obtained in small yields by heating the hydroxy acid is more easily prepared by the reaction between two molecules of chlor acetic acid and potassium hydroxide. As this reaction probably takes place in two steps, the hydroxy acetic acid being first formed from the chlor acetic acid, the formation of the ether may be represented as given. The resulting compound which, in the above case, is an ether of di-(hydroxy acetic acid) is known as di-glycolic acid hydroxy acetic acid itself being glycolic acid. It yields an anhydride by the loss of water from the two carboxyls. 

Also by an oxidation resulting in splitting the chain at the ketone group fructose yields hydroxy acetic acid, CH2OH—COOH and tri-hydroxy butyric acid, HOOC—CH(OH)—CH(OH)—CHoOH. 

This formation of single and double anhydrides from two molecules of an amino acid by loss of first one and then a second molecule of water is exactly analogous to the similar formation of anhydrides in the case of hydroxy acetic acid and all alpha hydroxy acids (p. 241). 

Mandellic Acid.—Mandellic acid is phenyl glycolic acid, CeHs— CH(OH)—COOH, phenyl hydroxy acetic acid. This constitution is proven by its synthesis from benzaldehyde by condensation with hydrogen cyanide and the hydrolysis of the resulting nitrile. 

Di-oxindole.— Similarly a di-hydroxy compound known as di-oxin-dole is obtained as a lactam anhydride from ortho-amino mandellic acid, ortho-amino phenyl hydroxy acetic acid. 

Disperse Accosoft 806 into water. Slowly add the hydroxy-acetic acid while mixing until product is homogeneous. Properties ... 

Subsequently, the same group reported an efficient AFC reaction of pyrroles having one electron-withdrawing group at the a,p or N-position with alkyl glyoxylates catalyzed by BINOL-Ti" complex 3 (Scheme 6.3). The reactions regioselectively afforded the desired pyrrole-hydroxy acetic acid derivatives 5 or 6 in good yields (up to 96%) and up to 97% ee. 

The widely used poly(glycolic acid) is a degradable polymer produced from another a-hydroxy acid not exhibiting chiral centers, glycolic acid (GA 2-hydroxy acetic acid). About 40 ktons was produced worldwide in 2011, and the demand of GA is... 

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