Efficient synthesis of (1R,2S) and (1S,2R)-2-aminocyclopentanecarboxylic acid ethyl ester derivatives in enantiomerically pure form

Dirhodium(II)-Catalyzed (3 + 2) Cycloaddition of the N-Arylaminocyclopropane with Alkene Derivatives

“…In addition, after treatment with the cis product 3ba with CAN, the desired β-amino ester 6a was obtained in 79% yield (see the SI). It was reported the 6a can undergo facile transformation to the chiral β-amino acid by chiral resolution …”

Scalable Synthesis of All Stereoisomers of 2-Aminocyclopentanecarboxylic Acid─A Toolbox for Peptide Foldamer Chemistry

“…In this case, a small amount of methylated byproduct was identified in the NMR spectra when the reaction was run in methanol. However, the main complication we faced with this compound was a partial loss (as previously observed) of debenzylated cis -amino ester during its recovery from dibenzoyl tartaric salt. The best solution appeared to be a decomposition of the salt ( R , S , S )- 2 •(D)-DBTA and isolation of free amine ( R , S , S )- 2 , followed by its treatment with HBr and hydrogenolysis of the newly formed salt ( R , S , S )- 2 •HBr under conditions identical to those of the trans -isomer (Scheme ).…”

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

“…The 1,2-dipolar cycloaddition of chlorosylfonyl isocyanate (CSI) to cyclopentene 1, cyclohexene 2, cycloheptene 3 and 1,5-cyclooctadiene 10 takes place regioselectively, in accordance with the Markovnikov orientation [35], resulting in racemic cis β-lactams 4, 5, 6, and 11. The synthesis were performed according to known methods (slight modifications for the synthesis of 6) [36][37][38].…”

“…The synthesis of racemic ethyl-2-aminocycloalkanecarboxylates 7-9 and 13 was carried out according to methods reported previously (the only exception is the synthesis of β-lactam 6), starting from 50 mmol cycloalkane [35][36][37][38]. 1 H-and 13 C-NMR as well as HRMS data on the enantiomeric derivatives were found to be similar to those for the racemates [12,[35][36][37][38][39]46,47]. Seven-membered β-lactam 6 was synthesized with a slightly modified literature procedure used for the synthesis of 4, 5, and 11 [38], as follows.…”