Poly(para-phenyleneethynylene)s as emtters in polymer LEDs

11 different dialkoxy- and dialkyl-poly(para-phenyleneethynylene)s (PPEs) featuring novel branched and literature described linear and branched side chains were prepared using a Sonogashira coupling. The side chains were of different length and branching character. The degree of polymerization of the PPEs ranged from Pn = 44–343 with polydispersities ranging from 1.5–3.1. Fairly simple OLED-stacks with up to three layers (electron injection, emitter layer, and hole injection) were produced. Depending upon the PPEs’ structure and the stack architecture but particularly the thickness of the emitting PPE-layer, a large increase in brightness up to 2.2 � 103 cd m�2 was observed, a significant improvement over earlier reported values

Bent <i>N</i>‑Heteroarenes

The syntheses and optical, electronic, and structural properties of a series of bent <i>N</i>-heteroarenes are described. The targets were obtained by condensation reactions of substituted aromatic <i>o</i>-diamines with 1,2-naphthoquinone and 1,2-anthraquinone in yields between 34 and 94%; naphthoquione-based products are generally formed in higher yields

Bent <i>N</i>‑Heteroarenes

The syntheses and optical, electronic, and structural properties of a series of bent <i>N</i>-heteroarenes are described. The targets were obtained by condensation reactions of substituted aromatic <i>o</i>-diamines with 1,2-naphthoquinone and 1,2-anthraquinone in yields between 34 and 94%; naphthoquione-based products are generally formed in higher yields