SYNTHESIS,STRUCTURE,AND π-DONOR PROPERTIES OF TRIS(ETHYLENEDIOXY)BENZENE AND BIS(ETHYLENEDIOXY)THIOPHENE

摘要

Tris(ethylenedioxy)benzene 3 and bis(ethylenedioxy)thiophene 4 have been synthesized starting from 2,3-dibromo-l,4-dioxene in 25 and 38 overall yields,respectively.These ethylenedioxy-fused benzene and thiophene can be easily oxidized to produce the corresponding radical cations 3~(·+)and 4~(·+)because of their high-lying HOMO levels.Interestingly,the radical cation 3~(·+)exhibits a fairly strong fluorescent emission at λ_(max)602 and 590 nm（Φf = 0.40 in MeCN and 0.50 in H2SO4).