
%0 Journal Article
%A Clark-Lewis, JW 
%A Jackman, LM 
%A Spotswood, TM 
%T Nuclear magnetic resonance spectra, stereochemistry, and conformation of flavan derivatives
%J Australian Journal of Chemistry
%D 1964/06/01
%V 17
%N 6
%P 632-648
%K 
%R https://doi.org/10.1071/CH9640632
%U https://www.publish.csiro.au/paper/CH9640632 
%X Chemical-shift and coupling-constant data for protons in 68 flavan derivatives are reported.   Coupling-constant data for interactions involving the 2-, 3-, and 4-protons have been used to define the configuration of the 2-, 3-, and 4-substituents and the conformation of the heterocyclic ring. It is shown that chemical-shift data for protons of the heterocyclic ring and of 3- and 4-acetoxyl groups are of little value in stereochemical studies.   Analysis of the absorptions of the aromatic protons shows that N.M.R. is useful for determining the oxygenation pattern in rings A and B. 
