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Green Strategies for the Preparation of Enantiomeric 5-8-Membered Carbocyclic β-Amino Acid Derivatives through CALB-Catalyzed Hydrolysis.

ABSTRACT: Candida antarctica lipase B-catalyzed hydrolysis of carbocyclic 5-8-membered cis β-amino esters was carried out in green organic media, under solvent-free and ball-milling conditions. In accordance with the high enantioselectivity factor (E > 200) observed in organic media, the preparative-scale resolutions of β-amino esters were performed in tBuOMe at 65 °C. The unreacted β-amino ester enantiomers (1R,2S) and product β-amino acid enantiomers (1S,2R) were obtained with modest to excellent enantiomeric excess (ee) values (ee_s > 62% and ee_p > 96%) and in good chemical yields (>25%) in one or two steps. The enantiomers were easily separated by organic solvent/H₂O extraction.

SUBMITTER: Shahmohammadi S

PROVIDER: S-EPMC9032184 | biostudies-literature | 2022 Apr

REPOSITORIES: biostudies-literature

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Green Strategies for the Preparation of Enantiomeric 5-8-Membered Carbocyclic β-Amino Acid Derivatives through CALB-Catalyzed Hydrolysis.

Shahmohammadi Sayeh S Faragó Tünde T Palkó Márta M Forró Enikő E

Molecules (Basel, Switzerland) 20220418 8

Candida antarctica lipase B-catalyzed hydrolysis of carbocyclic 5−8-membered cis β-amino esters was carried out in green organic media, under solvent-free and ball-milling conditions. In accordance with the high enantioselectivity factor (E > 200) observed in organic media, the preparative-scale resolutions of β-amino esters were performed in tBuOMe at 65 °C. The unreacted β-amino ester enantiomers (1R,2S) and product β-amino acid enantiomers (1S,2R) were obtained with modest to excellent enanti ...[more]

PMID: 35458798

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