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Circular Dichroism of 9,10‐Dihydrophenanthrene Derivatives Reveals both the Absolute Configuration and Conformation: A Novel Approach to Mislow's Helicity Rule
Author(s) -
Gawroński Jacek,
Grycz Piotr,
Kwit Marcin,
Rychlewska Urszula
Publication year - 2002
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/1521-3765(20020916)8:18<4210::aid-chem4210>3.0.co;2-7
Subject(s) - chromophore , absolute configuration , cotton effect , circular dichroism , chirality (physics) , helicity , chemistry , sign (mathematics) , biphenyl , stereochemistry , axial chirality , crystallography , physics , photochemistry , enantioselective synthesis , chiral symmetry , organic chemistry , mathematics , particle physics , mathematical analysis , nambu–jona lasinio model , quark , catalysis
The absolute configuration and the conformation of 9,10‐ trans ‐disubstituted 9,10‐dihydrophenanthrenes, known chiral metabolites of phenanthrene‐9,10‐oxide, have been determined by circular dichroism. The absolute configuration assignment is based on the sign of the long‐wavelength Cotton effect (A‐band), which is conformation invariant and originates from benzylic chirality. This provides a new interpretation of the Mislow biphenyl‐helicity rule for the case of the 9,10‐dihydrophenanthrene chromophore. The sign of the B‐band Cotton effect reflects the conformation of the biphenyl chromophore in 9,10‐dihydrophenanthrenes. It is shown that the origin of chiroptical properties of 9,10‐dihydrophenanthrenes is closely related to those of 5,6‐ trans ‐disubstituted 1,3‐cyclohexadienes.