Abstract:
:New chiral derivatizing reagents (CDAs) derived from trans-1,2-diaminocyclohexane, having an electron-deficient aromatic substituent (either an aromatic imide or 3,5-dinitrobenzamide) and rigid structure (either an amide or a urea linker), are reported. Significant shift differences of diastereotopic protons in the 1H NMR signals are observed for enantiomers of suitably protected alpha-amino acids, linked to CDA by a covalent bond. A simple, general model rationalizing the observed enantiomer discrimination and based on semiempirical conformational search is presented.
journal_name
Chiralityjournal_title
Chiralityauthors
Kaik M,Gajewy J,Grajewski J,Gawronski Jdoi
10.1002/chir.20435subject
Has Abstractpub_date
2008-03-01 00:00:00pages
301-6issue
3-4eissn
0899-0042issn
1520-636Xjournal_volume
20pub_type
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