Preparation and characterization of regioisomerically pure 1,7-disubstituted perylene bisimide dyes.
A detailed study on bromination and subsequent imidization of perylene bisanhydride with cyclohexylamine is reported. The present results reveal that previously reported 1,7-difunctionalized perylene bisimides are presumably contaminated with the respective 1,6 regioisomers. N,N'-Dicyclohexyl-1,7-dibromoperylene bisimide 1,7-3 is obtained for the first time in isomerically pure form, and its structure is unequivocally confirmed by X-ray analysis. By using regioisomerically pure 1,7-dibromoperylene bisimide 1,7-3, 1,7-dipyrrolidinylperylene bisimides 4a-c and 1,7-dipyrrolidinylperylene bisanhydride 5 as well as the unsymmetrically difunctionalized 1-bromo-7-pyrrolidinyl- and 1-cyano-7-pyrrolidinylperylene bisimides 7 and 8 are synthesized in good yield.
Würthner
Frank
F
Institutes of Organic Chemistry and Inorganic Chemistry, University of Würzburg, Am Hubland, 97074 Würzburg, Germany. wuerthner@chemie.uni-wuerzburg.de
Stepanenko
Vladimir
V
Chen
Zhijian
Z
Saha-Möller
Chantu R
CR
Kocher
Nikolaus
N
Stalke
Dietmar
D