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  • Dynamic B/N Lewis Pairs: Insights into the Structural Variations and Photochromism via Light‐Induced Fluorescence to Phosphorescence Switching
Title: Dynamic B/N Lewis Pairs: Insights into the Structural Variations and Photochromism via Light‐Induced Fluorescence to Phosphorescence Switching
Abstract Ultralong afterglow emissions due to room‐temperature phosphorescence (RTP) are of paramount importance in the advancement of smart sensors, bioimaging and light‐emitting devices. We herein present an efficient approach to achieve rarely accessible phosphorescence of heavy atom‐free organoboranes via photochemical switching of sterically tunable fluorescent Lewis pairs (LPs). LPs are widely applied in and well‐known for their outstanding performance in catalysis and supramolecular soft materials but have not thus far been exploited to develop photo‐responsive RTP materials. The intramolecular LPM1BNMnot only shows a dynamic response to thermal treatment due to reversible N→B coordination but crystals ofM1BNMalso undergo rapid photochromic switching. As a result, unusual emission switching from short‐lived fluorescence to long‐lived phosphorescence (rad‐M1BNM,τRTP=232 ms) is observed. The reported discoveries in the field of Lewis pairs chemistry offer important insights into their structural dynamics, while also pointing to new opportunities for photoactive materials with implications for fast responsive detectors.  more » « less
Award ID(s):
1954122
PAR ID:
10385119
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Angewandte Chemie International Edition
Volume:
61
Issue:
51
ISSN:
1433-7851
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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