Crystal Structure and Crystalline State Multiphotochromism Properties of a Fused Diarylethene Dimer

摘要

The crystal structure of fused photochromic diarylethene dimer,1,4-bis-[4-(4-[2-(5-phenyl)-2-methyl-thiophen-3-yl]-3,3,4,4,5,5-hexafluoro-cyclopent-1-enyl]-5-methyl-thiophen-2-yl) buta-l,3-diyne (1oo,C46H23F12S4) was determined by single-crystal X-ray diffraction analysis.This crystal belongs to the triclinic system,space group P(1) with a =7.546(3),b =8.869(3),c =16.196(5),a =98.000(4)°,β =100.803(4)°,y =98.449(4)°,Z =2,V=1037.6(6) (A)3,Dc =1.496mg/m3,μ =0.317,F(000) =474,the final R =0.0428 and wR =0.1199 for 4115 observed reflections (I ＞ 2σ(I)).Further study demonstrated this compound underwent reversible photochromism with color-switching between colorlessness and green in crystalline state.Upon 365 nm irradiation,the diarylethene shows one step photochromism to form isomer 1oc.When irradiated with 312 nm,the stepwise photocyclization reactions occurred in diarylethene dimer through the line of 1oo to 1oc to 1cc.