Syntheses of Four Enantiomers of 2,3-Diendo- and 3-Endo-aminobicyclo[2.2.2]oct-5-ene-2-exo-carboxylic Acid and Their Saturated Analogues

Abstract

J(H,H)coupling constants) and X-ray crystallography.

Enantiomeric Separation of Bicyclo[2.2.2]octane‐Based 2‐Amino‐3‐Carboxylic Acids on Macrocyclic Glycopeptide Chiral Stationary Phases

“…and 4b ) was achieved via isomerization, hydrogenation. and hydrolysis of the corresponding ester enantiomers . The stereochemistry and absolute configurations of the synthesized compounds were determined by nuclear magnetic resonance (NMR) spectroscopy and X‐ray crystallography …”

“…and hydrolysis of the corresponding ester enantiomers. 60 The stereochemistry and absolute configurations of the synthesized compounds were determined by nuclear magnetic resonance (NMR) spectroscopy and X-ray crystallography. 59,60 The difference between analytes a and b is the difference in the steric orientation in positions 1, 2, 3, and 4 (…”

Bicyclic β-amino acids

“…81 Enantiodivergent versions of some of these methods were also reported. 82 Asymmetric synthesis of derivatives of the amino acids 98a,b and 99 relied on Diels -Alder reaction with the use of solidsupported dienophile 104 (Scheme 29). 84 A mixture of adducts 105a-d was obtained in this reaction, which was cleaved from the resin and hydrolyzed to give mixture of all four stereoisomers of 98.…”

“…81 Amino acid 95b was prepared via epimerisation of derivative of 95a. 82 Moreover, amino acids 96 and 97 were obtained following the synthetic schemes described above for their analogues 37a and 38 (see Schemes 13 and 14). 81 Enantiodivergent versions of some of these methods were also reported.…”

Syntheses and transformations of alicyclic β-aminohydroxamic acids

“…[77] Resolution via diastereomeric salt formation, for instance, is still useful for the production of enantiomerically pure esters on a laboratory scale. [78] Resolution with one equiv. of the resolving agent (Pasteur's method) is the most convenient when working with small amounts of the racemate.…”