77287-29-7Relevant academic research and scientific papers
Synthesis of Optically Active Chloro Alkanoic Esters
Azzena, Ugo,Delogu, Giovanna,Melloni, Giovanni,Piccolo, Oreste
, p. 4555 - 4558 (1989)
The stereospecific synthesis (optical yield up to 94percent) of optically active (R)-alkyl-2-chloropropionate and (S)-alkyl-3-chlorobutanoate by the action of AlCl3 on the corresponding (S)-2-mesyloxy- and (R)-3-mesyloxy-derivatives is described.
Method for preparing (R)-(+)-2-(4-hydroxyphenoxy) propionic acid in micro-structure reactor
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Paragraph 0023-0025, (2018/06/21)
The invention relates to the field of fine chemical engineering, in particular, a method for preparing (R)-(+)-2-(4-hydroxyphenoxy) propionic acid in a micro-structure reactor. The provided method utilizes a micro-structure reactor to prepare R)-(+)-DHPPA, overcomes the shortages of a conventional method, and has the following advantages: (1) the byproduct is few, and the yield is high; (2) the operation is simple, and continuous and controllable production is realized; and (3) according to the production needs, massive production can be realized, and there is no amplification effect.
A synthetic S-2-chloropropionic acid methyl ester method
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Paragraph 0036-0039, (2017/03/17)
The invention discloses a method for synthesizing S-2-methyl chloropropionate. The method comprises the following steps of: (1) preparing a Vilmerier reagent: adding a chlorinating agent into a reaction kettle, adding short chain aliphatic series dropwise to replace amide to serve as a solvent, and reacting under the stirring condition to obtain a Vilmerier reagent solution; (2) synthesizing S-2-methyl chloropropionate: adding a small amount of solvent into the Vilmerier reagent solution obtained in the step 1 to obtain a mixed solution, adding R-methyl lactate into the mixed solution dropwise, and stirring to perform chlorination to obtain a product solution, namely the S-2-methyl chloropropionate solution; and (3) washing the S-2-methyl chloropropionate solution obtained in the step 2, desolventizing and distilling to obtain the product S-2-methyl chloropropionate. The synthesis method is mild in reaction condition, easy to operate, low in environmental pollution and suitable for large-scale industrialized production.
A substrate-driven approach to determine reactivities of α,β-unsaturated carboxylic esters towards asymmetric bioreduction
Tasnádi, Gábor,Winkler, Christoph K.,Clay, Dorina,Sultana, Nargis,Fabian, Walter M. F.,Hall, Mélanie,Ditrich, Klaus,Faber, Kurt
experimental part, p. 10362 - 10367 (2012/10/08)
The degree of C=C bond activation in the asymmetric bioreduction of α,β-unsaturated carboxylic esters by ene-reductases was studied, and general recommendations to render these "borderline-substrates" more reactive towards enzymatic reduction are proposed. The concept of "supported substrate activation" was developed. In general, an additional α-halogenated substituent proved to be beneficial for enzymatic activity, whereas β-alkyl or β-aryl substituents were detrimental for the reactivity of nonhalogenated substrates, and α-cyano groups showed little effect. The alcohol moiety of the ester functionality was found to have a strong influence on the reaction rate. Overall, activities were determined by both steric and electronic effects. Biotransformation: The asymmetric bioreduction of α,β-unsaturated carboxylic esters by ene-reductases could be tuned by varying the degree of C=C bond activation (see scheme). An additional α-halogenated substituent proved to be beneficial for enzymatic activity, whereas β-alkyl or β-aryl substituents were detrimental for the reactivity of nonhalogenated substrates. Copyright
Optically active maleimide derivatives and polymaleimides for use as chiral adsorbent in chromatography
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Page 12; 13, (2010/02/09)
An optically active maleimide dericative represented by the following formula (1): as well as the polymer synthesized therefrom. The polymers are useful as chival adsorbents in chomatography.
Direct Organocatalytic Asymmetric α-Chlorination of Aldehydes
Halland, Nis,Braunton, Alan,Bachmann, Stephan,Marigo, Mauro,Jorgensen, Karl Anker
, p. 4790 - 4791 (2007/10/03)
The direct organocatalytic enantioselective α-chlorination of aldehydes has been developed. The reaction proceeds for a series of different aldehydes with NCS as the chlorine source using easily available catalysts such as L-proline amide and (2R,5R)-diphenylpyrrolidine. The α-chloro aldehydes are obtained in up to 99% yield and up to 95% ee. The synthetic utility of the enantioselective α-chlorination of aldehydes is demonstrated by transformation of the α-chloro aldehydes to the corresponding α-chloro alcohols (>90% yield) by standard reduction and further transformation to both a terminal epoxide and amino alcohol, both obtained without loss of optical purity. Oxidation of the α-chloro aldehydes followed by esterification gave optically active α-chloro esters without loss of optical purity. It is demonstrated that these optically active α-chloro esters can be converted into nonproteinogenic amino acids in overall high yields, maintaining the enantiomeric excess obtained in the catalytic enantioselective α-chlorination step. Copyright
Optical methyl 2-chloropropionate synthesis by decomposition of methyl 2-(chlorocarbonyloxy)propionate with hexaalkylguanidinium chloride hydrochloride
Violleau, Frédéric,Thiébaud-Roux, Sophie,Borredon, Elisabeth,Le Gars, Pierre
, p. 8607 - 8612 (2007/10/03)
The decomposition of methyl S-(-)-2-(chlorocarbonyloxy)propionate in the presence of hexaalkylguanidinium chloride hydrochloride was confirmed to correspond to a nucleophilic substitution of the second order. However, racemization occured by the contact between the catalyst and methyl R-(+)-2-chloropropionate (I). This phenomenon is caused by the exchange between the chloride ion from catalyst and the chlorine atom of (I) according to a SN2 mechanism as well.
A NEW CHIRAL HOST COMPOUND 10,10'-DIHYDROXY-9,9'-BIPHENANTHRYL. OPTICAL RESOLUTION OF PROPIONIC ACID DERIVATIVES, BUTYRIC ACID DERIVATIVES, AND 4-HYDROXYCYCLOPENT-2-EN-1-ONE DERIVATIVES BY COMPLEXATION
Toda, Fumio,Tanaka, Koichi
, p. 1807 - 1810 (2007/10/02)
Optically active 10,10'-dihydroxy-9,9'-biphenanthryl was designed as a new chiral host compound for optical resolution of guest compounds, and was found to be wery effective for resolution of the title guest compounds.
