
TY  - JOUR
A1  - Bognar, R 
A1  - Clark-Lewis, JW 
A1  - Liptakne-Tokes, A 
A1  - Rakosi, M 
T1  - Resolution of 4-aminoflavan into its optical isomers; nuclear magnetic resonance spectra of 4-aminoflavan and 3-aminoflavanone derivatives
JF  - Australian Journal of Chemistry
JO  - Aust. J. Chem.
Y1  - 1970
VL  - 23
IS  - 10
SP  - 2015
EP  - 2025
KW  - 
UR  - https://doi.org/10.1071/CH9702015 
N2  - (±)-2,4-cis-4-Aminoflavan obtained by reduction of 4-oximinoflavan has been resolved into enantiomeric forms by fractional crystallization of its amine salts with (+)-camphor-10-sulphonic acid and with (-)-di-O-benzoyltartaric acid. The pairs of diastereoisomeric salts thus separated were converted into (+)- and (-)-2,4-cis-4-aminoflavan hydrochlorides, from which the free bases and the optically active N-acetyl and N-benzoyl derivatives were prepared. N.m.r. data unequivocally establish the 2,4-cis configuration of all these 4-substituted flavan derivatives. 3-Aminoflavanone prepared by the Neber rearrangement of 4-oximinoflavan, and also by controlled catalytic hydrogenation of 3-oximinoflavanone, is shown from N.M.R. data on suitable derivatives to have the 2,3-trans configuration. 
ER  -

