73246-45-4Relevant articles and documents
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 (2002)
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 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.
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