Reduced band gap dithieno[3,2-b:2',3'-d]pyrroles: new n-type organic materials via unexpected reactivity.
Direct addition of tetracyanoethylene to N-(p-hexylphenyl)dithieno[3,2-b:2',3'-d]pyrrole yields not only the aromatic mono- and bis-tricyanovinyl-substituted products but also a quinoidal product with dicyanomethylene groups. The analogous reaction with dithieno[3,2-b:2',3'-d]thiophene yields exclusively the aromatic mono-tricyanovinyl product. The aromatic and quinoidal products possess red-shifted absorptions, increased electron affinities, and favorable pi-stacking motifs in comparison to the unsubstituted oligomers.
Pappenfus
Ted M
TM
Division of Science and Mathematics, University of Minnesota, Morris, MN 56267, USA. pappe001@morris.umn.edu
Hermanson
Bethany J
BJ
Helland
Tyler J
TJ
Lee
Garett G W
GG
Drew
Steven M
SM
Mann
Kent R
KR
McGee
Kari A
KA
Rasmussen
Seth C
SC