Synthesis of enantiomerically pure helicene like bis-oxazines from atropisomeric 7,7'-dihydroxy BINOL: Preliminary measurements of the circularly polarized luminescence.
Racemic sample of 2,2',7,7'-tetrahydroxy-1,1'-binaphthyl was resolved with (S)-proline and the separated enantiomers were independently converted to atropisomeric bis-oxazines by aromatic Mannich reaction. These chirally pure oxazines were then converted to the helicene like cyclic ethers. The Circularly Polarized Luminescence (CPL) profile was consistent with the isolation of the targeted helical-like molecules in optically pure form, prepared from the achiral primary amines. The compounds of interest displayed active and opposite CPL activities for each sets of the helicene like isomers (P)-/(M)-3and (P)-/(M)-5.
Department of Chemistry, Faculty of Science, M. S. University of Baroda, Vadodara 390 002, India.
M Shyam
MS
Sundar
Department of Chemistry, Faculty of Science, M. S. University of Baroda, Vadodara 390 002, India.
Harish R
HR
Talele
Department of Chemistry, Faculty of Science, M. S. University of Baroda, Vadodara 390 002, India.
Hemant M
HM
Mande
Department of Chemistry, Faculty of Science, M. S. University of Baroda, Vadodara 390 002, India.
Ashutosh V
AV
Bedekar
Department of Chemistry, San José State University, San José, California 95192-0101, USA.
Roberto C
RC
Tovar
Department of Chemistry, San José State University, San José, California 95192-0101, USA.
Gilles
G
Muller
CD and CPL study; Resolution; bis-oxazine