Perylene bisimide atropisomers: synthesis, resolution, and stereochemical assignment.
The macrocyclization of the tetra-hydroxyphenoxy-substituted perylene bisimide 4 bearing two (R)-configured 2-octyl substituents in the imide positions by etherification with diethylene glycol ditosylate afforded both the diagonally bridged (1,7- and 6,12-linkage) and laterally bridged (1,12- and 6,7-linkage) regioisomers 6 and 7. The atropo-diastereomers of the diagonally bridged macrocycle 6 were separated by semipreparative HPLC on a chiral column, and their absolute configurations were determined by circular dichroism (CD) spectroscopy in combination with quantum chemical CD calculations. The isolated epimers (P,R,R)-6 and (M,R,R)-6 represent the first examples of diasteriomerically pure perylene bisimide atropisomers. The optical and chiroptical properties of these epimers were investigated by UV/vis, fluorescence, and CD spectroscopy, and their conformational properties have been explored by temperature-dependent 1H NMR studies.
Osswald
Peter
P
Universität Würzburg, Institut für Organische Chemie, Am Hubland, 97074 Würzburg, Germany.
Reichert
Matthias
M
Bringmann
Gerhard
G
Würthner
Frank
F
D002625:Chemistry, Organic / Q000379:methods*; D002851:Chromatography, High Pressure Liquid; D002942:Circular Dichroism; D007094:Imides / Q000138:chemical synthesis / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008956:Models, Chemical; D008958:Models, Molecular; D015394:Molecular Structure; D010569:Perylene / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry; D011789:Quantum Theory; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet; D013237:Stereoisomerism
D007094:Imides; C510697:perylene bisimide; D010569:Perylene