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Mechanofluorochromic Behaviors of Salicylaldimine Difluoroboron Complexes
Author(s) -
Yang Hao,
Ye Kaiqi,
Sun Jingbo,
Gong Peng,
Lu Ran
Publication year - 2017
Publication title -
asian journal of organic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.846
H-Index - 44
eISSN - 2193-5815
pISSN - 2193-5807
DOI - 10.1002/ajoc.201600482
Subject(s) - chemistry , combinatorial chemistry , photochemistry
We have synthesized a series of salicylaldimine difluoroboron complexes that contain carbazole moieties. Substituents on the carbazole and on the benzene rings of the salicylaldimine moiety influenced the intramolecular charge transfer (ICT) emissions of these complexes. Interestingly, the synthesized difluoroboron complexes emitted strong light in the solid state under UV irradiation and exhibited reversible mechanofluorochromism behavior. The emission of a pristine sample of 3‐[4‐(3,6‐di‐ tert ‐butyl‐9 H ‐carbazol‐9‐yl)phenyl]‐2,2‐difluoro‐2 H ‐2λ 4 ,3λ 4 ‐benzo[ e ][1,3,2]oxazaborinine ( TCH ) at 488 nm redshifted to 571 nm upon grinding, and the ground powder exhibited an orange emission. Fuming with dichloromethane (DCM) or heating at 200 °C for 2 min led to the recovery of the original solid state that emitted a bluish‐green light. XRD patterns illustrate that the mechanofluorochromism features are reasonable for the transformation between the crystalline and amorphous states.