2983-36-0Relevant academic research and scientific papers
Influence of the position of the substituent on the efficiency of lipase-mediated resolutions of 3-aryl alkanoic acids
Deasy, Rebecca E.,Moody, Thomas S.,Maguire, Anita R.
, p. 1480 - 1487 (2013/12/04)
Hydrolase-catalysed kinetic resolutions to provide enantioenriched α-substituted 3-aryl alkanoic acids are described. (S)-2-Methyl-3- phenylpropanoic acid (S)-1a was prepared in 96% ee by Pseudomonas fluorescens catalysed ester hydrolysis, while, Candida antarctica lipase B (immob) resolved the α-ethyl substituted 3-arylalkanoic acid (R)-1b in 82% ee. The influence of the position of the substituent relative to the ester site on the efficiency and enantioselectivity of the biotransformation is also explored; the same lipases were found to resolve both the α- and β-substituted alkanoic acids. Furthermore, the steric effect of substituents at the C2 stereogenic centre relative to that for their C3 substituted counterparts on the efficiency and stereoselectivity is discussed.
Highly enantioselective iridium-catalyzed hydrogenation of α,β-unsaturated esters
Li, Jia-Qi,Quan, Xu,Andersson, Pher G.
, p. 10609 - 10616 (2012/11/07)
α,β-Unsaturated esters have been employed as substrates in iridium-catalyzed asymmetric hydrogenation. Full conversions and good to excellent enantioselectivities (up to 99 % ee) were obtained for a broad range of substrates with both aromatic- and aliphatic substituents on the prochiral carbon. The hydrogenated products are highly useful as building blocks in the synthesis of a variety of natural products and pharmaceuticals. Asymmetric hydrogenation: A variety of α,β-unsaturated esters were hydrogenated with high enantioselectivities (see scheme). The hydrogenated products have been used in synthetic transformations as well as in formal total syntheses. Copyright
Iodo-aryl carbonates for use in methods in radiography
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, (2008/06/13)
A method for using iodo-aryl carbonates, such as for example, p-iodo-benzyl carbonates, p-iodo-sec-phenethyl carbonates, p-iodo-phenethyl carbonates, p-iodo-phenyl carbonates, 3-(p-iodophenyl)propyl carbonates, 3-(p-iodophenyl)butyl carbonates, 2-(p-iodobenzyl)butyl carbonates and 2-(p-iodobenzyl)-n-hexyl carbonates, to provide radiopaques for various radiography purposes in connection with such techniques as X-ray applications including myelography, salpingography, lymphography and bronchography. The method first comprises selecting a compound generally categorized as a carbonate and having the general formula STR1 wherein R represents an alkyl group having from 1 to 10 carbon atoms and R' represents an iodinated phenyl linked directly to the ester oxygen or through an alkyl chain consisting of 1 to 3 carbon atoms. An effective amount of a pharmaceutically acceptable carbonate, as defined herein, is then placed into the subject body cavity and the particular X-ray or other study performed of this area.
Iodine containing organic carbonates for use as radiographic agents
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, (2008/06/13)
Iodo-aryl carbonates, such as for example, p-iodo-benzyl carbonates, p-iodo-sec-phenethyl carbonates, p-iodo-phenethyl carbonates, p-iodo-phenyl carbonates, 3-(p-iodophenyl)propyl carbonates, 3-(p-iodophenyl)butyl carbonates, 2-(p-iodobenzyl)butyl carbonates and 2-(p-iodobenzyl)-n-hexyl carbonates, for use as radiographic media in connection with such techniques as x-ray applications including myelography, salpingography, lymphography and bronchography. An effective quantity of iodinated organic carbonate provides x-ray contrast, and the compounds of the invention may be characterized generally as carbonates having the general formula STR1 wherein R represents an alkyl group having from 4 to 10 carbon atoms and R' represents an iodinated phenyl linked to the ester oxygen through an alkyl chain consisting of 1 to 3 carbon atoms.
