66423-08-3Relevant articles and documents
PROCESS FOR PRODUCING OPTICALLY ACTIVE 2-SUBSTITUTED CARBOXYLIC ACID
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Page 20, (2010/11/30)
The present invention relates to a process for efficiently producing an optically active 2-bromocarboxylic acid and an optically active 2-sulfonyloxycarboxylic acid, which are important in the production of medicinal compounds and so forth. An optically active 2-sulfonyloxycarboxylic acid ester is subjected to deprotection under acid conditions to obtain an optically active 2-sulfonyloxycarboxylic acid. A metal bromide is caused to act on the acid to brominate it with configuration inversion at position 2 to thereby produce an optically active 2-bromocarboxylic acid. The resultant optically active 2-bromocarboxylic acid is isolated/purified by subjecting it to a step in which the acid is crystallized and separated as a salt with a base. Thus, an optically active 2-bromocarboxylic acid having a high chemical purity and high optical purity can be produced.
Friedel-Crafts alkylation of aromatic compounds with optically active 2-(mesyloxy)propionates. Synthesis of the optically active anti-inflammatory agent (S)-2-(4-isobutylphenyl)propionic acid
Garot, C.,Javed, T.,Mason, T. J.,Turner, J. L.,Cooper, J. W.
, p. 755 - 758 (2007/10/03)
Alkylation of benzene, toluene and isobutylbenzene with (S)-2-mesyloxypropanoate substrates 2a-g in the presence of aluminium chloride, affords the corresponding (S)-methyl-2-phenylpropionates in good chemical yields under ultrasound mediated conditions.This method leads to the synthesis of (S)-brufen in 50percent yield within 2 hours at 40 deg C compared with only 17percent under conventional conditions when isobutylbenzene was treated with 2b, thus leading to a significant improvement in selectivity for (S)-ibuprofen (40percent to 59percent).
Alkali metal fluorides as efficient fluorinating agents. Enantiocontrolled synthesis of 2-fluoroalkyl carboxylates and 1-fluoroalkyl benzenes
Fritz-Langhals
, p. 981 - 986 (2007/10/02)
Potassium fluoride and cesium fluoride in formamide, N-methylformamide, or acetamide are efficient fluorinating agents. They can be used for the enantiocontrolled synthesis of 2-fluorocarboxylic acids 1a and 1-fluoroalkyl benzenes 1b from the correspondin
Preparation of Methyl 2-Arylpropanoates by the Reaction of 2-Hydroxypropiophenone Dimethyl Acetals with Sulfuryl Chloride in the Presence of an Amide or a Weak Base
Yamauchi, Takayoshi,Hattori, Kaneaki,Nakao, Kenji,Tamaki, Kentaro
, p. 4015 - 4018 (2007/10/02)
Treatment of 2-hydroxypropiophenone dimethyl acetals (1; R=H, i-Bu, OMe, Ph, Br) with sulfuryl chloride in the presence of an amide or a weak base affords methyl 2-arylpropanoates (2) in good to excellent yields via 1,2-aryl migration of 1.The hydrolysis of 2 leads to the corresponding acids some of which are pharmaceutically important compounds having nonsteroidal anti-inflammatory and analgesic acivities.The aryl migration proceeds stereospecifically with complete inversion of configuration at the β-carbon atom.
Preparation of α-arylalkanoic acids
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, (2008/06/13)
Pharmaceutically useful optically active α-arylalkanoic acids or esters, ortho esters, or amides thereof are stereoselectively prepared by contacting an aryl magnesium Grignard reagent with an optically active α-substituted acyl halide to form the optically active aryl α-substituted alkyl ketone, which is ketalized and rearranged to the desired optically active α-arylalkanoic acid or the corresponding ester, ortho ester or amide. In an alternate embodiment, the aryl α-substituted alkyl ketone is reduced to the corresponding alkanol, which is rearranged to the α-arylalkanal. The alkanal so produced is converted to the desired optically active α-arylalkanoic acid by conventional methods.
Results of Process Research. I. Synthesis of O-propionyl>-acetone oxime
Imfeld, Marquard,Suchy, Milos,Vogt, Peter,Lukac, Teodor,Schlageter, Markus,Widmer, Erich
, p. 1233 - 1241 (2007/10/02)
Efficient and simple procedures for the preparation of O--propionyl>-oxime derivatives 7b-e have been developed.The alkylation of 4-phenol (11) with 7d, the final step of a technical synthesis of 1, has been studied in detail.
