摘要
Main observation and conclusion In this paper,two novel donor-acceptor(D-A)macrocyclic compounds 5 and 7 were successfully synthesized by post-functionalization of a planar dimer macrocycle(1)and a highly twisted trimer macrocycle(2),respectively,via controllable oxidation of methoxy groups and condensation between diketones and phenylenediamine in succession.Compared with unembellished 9,10-dimethoxyphenanthrene,the resultant dibenzo[a,c]phenazine motif is electron-deficient rather than electron-rich,yielding two D-Aπ-conjugated macrocycles with more contractive energy gaps.Density functional theory(DFT)calculations further support the unequivocal evidence of the D-A properties of macrocycles 5 and 7.The difference of their photophysical properties was investigated by the aid of ultraviolet-visible absorption and fluorescence spectrophotometers.Furthermore,the stacking patterns of 7 and its contrastπ-conjugated macrocycle trimer(2)were compared via the analysis of X-ray single crystal,in which the electron-deficient dibenzo[a,c]phenazine unit provides extra interaction sites,resulting in orderly arrangement of 7 in the solid state.
基金
supported by the Hong Kong Research Grants Council(HKU 27301720).J.L.is grateful for the funding support from ITC to the S.K.L.We thank the UGC funding administered by The University of Hong Kong(HKU)
supporting the Time-of-Flight Mass Spectrometry Facilities under the Support for Interdisciplinary Research in Chemical Science,and HKU University Development Fund for funding the X-Ray Diffractometer Facilities.We acknowledge the computer cluster(HPC2015)
HKU for generous allocations of compute resources.