PROBLEM TO BE SOLVED: To provide a novel method for manufacturing a salt of α-hydroxy acid as an intermediate for synthesizing α-hydroxy acid derivatives which promotes carboxylation promptly by the COsupplementation reaction even if the substrate having
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Paragraph 0054-0056
(2018/02/14)
Kinetic resolution of mandelate esters via stereoselective acylation catalyzed by lipase PS-30
By using lipase PS-30 as catalyst, the kinetic resolution of a series of racemic mandelate esters has been achieved via stereoselective acylation. The value of kinetic enantiomeric ratio (E) reached up to 197.5. Substituent effect is briefly discussed.
Chen, Peiran,Yang, Wenhong
p. 2290 - 2294
(2014/04/17)
Synthesis of arylglycine and mandelic acid derivatives through carboxylations of α-amido and α-acetoxy stannanes with carbon dioxide
Incorporation reactions of carbon dioxide (CO2) with N-Boc-α-amido and α-acetoxy stannanes were developed using CsF as a mild tin activator. Monoprotected α-amido stannanes could be used, and the corresponding arylglycine derivatives were obtained in moderate-to-high yields under 1 MPa (10 atm) of CO2 pressure. α-Acetoxy stannanes also underwent carboxylation to afford mandelic acid derivatives in excellent yields under ambient CO2 pressure. Both transformations enabled the synthesis of α-tertiary and α-quaternary carboxylic acid derivatives. In addition, the chirality of (S)-N-tert-butylsulfonyl-α- amido stannanes was transferred with up to 90% inversion of configuration at 100 °C.