
TY  - JOUR
A1  - Katekar, GF 
A1  - Moritz, AG 
T1  - The hydroxyl stretching frequencies and conformations of Flavan-4-ols and Thiaflavan-4-ols
JF  - Australian Journal of Chemistry
JO  - Aust. J. Chem.
Y1  - 1969
VL  - 22
IS  - 11
SP  - 2337
EP  - 2342
KW  - 
UR  - https://doi.org/10.1071/CH9692337 
N2  - The hydroxyl stretching frequencies of some 2,4-cis and 2,4-trans flavan-4-ols, thiaflavan-4-ols, and related compounds have been measured in dilute carbon tetrachloride solution. Characteristic frequencies are observed at 3626±2 cm-1 (free hydroxyl), 3616±1, and 3597±2 cm-1. The 3616 and 3597 cm-1 bands are assigned to pseudo-axial and pseudo-equatorial hydroxyl groups respectively. Evidence is presented to show that the frequency shifts arise from differences in the interaction of the hydroxyl group with the &#960;-electrons of the fused benzene ring, and that these flavans and thiaflavans exist in half- chair, rather than sofa conformations. 
ER  -

