Propeller Ultralong Room Temperature Phosphorescence: New Aspect of Triphenylphosphine Derivatives

Abstract Triphenylphosphine ( Ph 3 P ) derivatives are used as indispensable ligands in catalytic chemistry, as represented by Crab‐tree's catalyst, Wilkinson's catalyst, and Grubbs’ catalyst. A serendipitous finding that simple substituted triphenylphosphine (tris(2‐methoxyphenyl)phosphine, RTP‐SDFMU‐1 ) exhibits ultralong room temperature phosphorescence (RTP) in air, with afterglows of ≈6 s, is described herein. The phosphorescence properties of Ph 3 P derivatives without heavy atoms and/or carbonyl groups are remarkable both in polycrystalline state and powder state. A study with 25 Ph 3 P derivatives and single crystal diffraction analysis indicate that the number of n electrons in phenyl ring and the packing of molecules in solid state are crucial for their ultralong RTP. The present discovering may renew the general view of ultralong organic RTP molecules and open a window for the phosphorescence research of Ph 3 P derivatives.