259856-83-2Relevant academic research and scientific papers
AN ENANTIOSELECTIVE PROCESS FOR THE SYNTHESIS OF (2S,4R)-4-HYDROXYPIPECOLIC ACID
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Page/Page column 23, (2016/08/23)
The present invention relates to an improved process for synthesis of 4-hydroxy pipecolic acid. The present invention relates to an improved enantioselective process for the synthesis of (2S,4R)-4-hydroxypipecolic acid via Co(III) (salen)-catalyzed two stereocentered Hydrolytic Kinetic Resolution (HKR) of racemic 1,3-azido epoxide with good yields and high optical purity without any protecting groups. 10 31
Asymmetric synthesis of the four stereoisomers of 4-hydroxypipecolic acid
Davis,Fang,Chao,Burns
, p. 2106 - 2112 (2007/10/03)
The asymmetric synthesis of all four stereoisomers of 4-hydroxypipecolic acid (1) from the polyfunctionalized chiral building blocks δ-amino β-keto esters (S(S),R)-(+)-5 or (R(S),S)-(-)-5 is described. Key steps in the synthesis are the stereoselective reductions of b-phenylpiperidine-2,4-dione (6) and N-sulfinyl δ-amino β-keto esters 5 to cis 4-hydroxy 2-piperidinone 7 and syn-δ-amino β-hydroxy ester 9, respectively. The only protecting/deprotecting group chemistry required is related to the oxidation step.
A new route to (2S,4R)- and (2R,4S)-4-hydroxypipecolic acid
Haddad, Mansour,Larcheveque, Marc
, p. 4231 - 4237 (2007/10/03)
Both enantiomers of cis-4-hydroxypipecolic acid have been prepared by asymmetric synthesis using (S)- or (R)-glycidol as the chiral source, and involving a stereoselective hydrogenation of a six-membered cyclic imine. The latter is obtained by reduction and cyclization of a cyano β-hydroxy ketone.
