98%
921
2 minutes
20
Chiral amines and amino alcohols form an important category of molecules employed in the designing of new drugs and catalyst. Herein, we present a helically-twisted stereodynamic dialdehyde probe 1 for the determining of absolute configuration, and enantiomeric excess of chiral amine and amino alcohols. Probe 1 is based on the pyridine-2,6-dicarboxamide (PDC) core and undergoes rapid interconversion between the P- and M- conformers. However, upon imine formation with chiral amines, probe 1 gets locked it in a single conformer majorly. This induces a strong CD signal in addition to changes in the UV-vis and fluorescence signals. The CD spectral change allowed for quantitative enantiomeric excess determination of chiral amines. Circular polarized luminescence (CPL) spectra having the g of 1×10 was obtained upon imine formation between probe 1 and diamine 2. Single crystal X-ray diffraction studies (SCXRD) confirmed the twisted conformation in 1@(R)-4 and 1@(S)-4, stabilized by intramolecular hydrogen bonding between bound imine nitrogen and proximate amide group.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1002/asia.202401376 | DOI Listing |
Anal Chem
September 2025
School of Pharmaceutical Sciences, Anhui Medical University, Hefei 230032, China.
Carboxylic enantiomers are prevalent in living organisms and synthetic samples that exhibit important biological properties. The profiling of carboxylic enantiomers is beneficial for monitoring physiological states and further unraveling the metabolism mechanisms between carboxylic enantiomers and diseases. In this study, pairs of light and heavy isotope reagents, ()-(3-aminopiperidin-1-yl) phenyl-methanone/-()-(3-aminopiperidin-1-yl) phenyl-methanone (APMA/-APMA), were synthesized and applied to tag the enantiomers of carboxylic metabolites and drugs.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
September 2025
State Key Laboratory of Physical Chemistry of Solid Surfaces, Key Laboratory of Chemical Biology of Fujian Province, and College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, China.
The enantioselective construction of quaternary carbon stereocenters bearing amine functionalities represents a significant challenge in organic synthesis despite their prevalence in pharmaceutically active compounds. Herein, we report a versatile metallaphotoredox platform for the asymmetric incorporation of amine fragments onto quaternary carbons via coupling of alkene-tethered aryl bromides with readily available α-silylamines. This transformation proceeds under mild conditions without requiring organometallic reagents or stoichiometric reductants.
View Article and Find Full Text PDFChem Commun (Camb)
September 2025
Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, CH-3012 Bern, Switzerland.
Iron complexes bearing chiral salicyloxazoline (Salox) ligands catalyze the enantioselective intramolecular C-H bond amination of alkyl azides, reaching 58-76% ee for benzylic C-H bonds. Further, for the first time aliphatic C-H bond amination is demonstrated (∼40% ee). This class of catalysts even activates primary aliphatic C-H bonds, albeit with moderate ee.
View Article and Find Full Text PDFChemSusChem
September 2025
Organic Chemistry Institute, University of Münster, Corrensstraße 36, 48149, Münster, Germany.
A three-step, one-pot, sequential cascade starting from simple feedstocks to increase complexity toward value-added chiral synthetic building blocks is reported. This is achieved by precisely integrating organic photocatalysis and noncovalent organocatalysis, often operating at dissimilar conditions and reaction media. In particular, this strategy is used to enable the direct transformation of readily available benzylic substrates, such as methylbenzenes, benzyl alcohols, or amines, into enantioenriched α-aminonitriles by benzylic CH photooxidation to their corresponding aldehydes, followed by in situ imine formation and final asymmetric organocatalytic Strecker reaction.
View Article and Find Full Text PDFInorg Chem Front
September 2025
Department of Chemistry, University of Copenhagen Universitetsparken 5 2100 Denmark
We herein demonstrate the synthesis of a pair of enantiomerically pure Yb complexes by post-functionalisation of the parent Yb complex condensation with an enantiomerically pure chiral amine. The enantiomeric pair is structurally characterised by single crystal and powder X-ray diffraction, showing that it crystalises in the 222 Sohncke space group with Flack parameters close to zero, which confirms their enantiopurity. Circular Dichroism (CD) and absorption spectroscopies in the NIR reveal sharp F → F f-f transitions, with values up to 0.
View Article and Find Full Text PDF