TITLE:
A Concept for a Novel Test for Chemical Parity
AUTHORS:
Heinz Langhals, Oswald Krotz
KEYWORDS:
Chirality, Parity, Circular Dichroism, UV/Vis Spectroscopy, Racemates
JOURNAL NAME:
Green and Sustainable Chemistry,
Vol.8 No.4,
October
29,
2018
ABSTRACT: Deviations from chemical parity (PV) were evaluated with the search for very small enantiomeric excesses in a racemate prepared from non chiral materials and were detected by means of the circular dichroism (CD). Thus, intensely light-absorbing perylenebiscarboximides were attached to axially chiral biphenyls for the amplification of CD effects by exciton interactions of the adjacent chromophores. A rapidly racemising system was applied for the exclusion of artifacts and compared with an analogous with locked chirally. A very slight enantiomeric excess was detected for the (M) enantiomer. Application of the method for other systems was suggested and relations to natural products discussed.