Synthesis of new polyconjugated molecules with biphenyl, dibenzothiophene, carbazole and phenanthrene units

Vyacheslav K Olkhovik,Vitalii G Petushok,Dmitrii A Vasilevskii,Galina V Kalechyts,Yurii V Matveienko,Andrei A Pap,Nikolay A Halinouski,Andrei G Baran,Mikael Begtrup

doi:10.3998/ark.5550190.0009.908

Abstract

The simple methods of synthesis of hardly accessible substituted biphenyl, dibenzothiophene, carbazole and phenanthrene derivatives were elaborated starting from dimethyl 4,4’biphenyldicarboxylate. The series of new luminophores with extended π-conjugated chains based on combinations of biphenyl, carbazole, dibenzothiophene, phenanthrene fragments and alternating phenyl, vinyl or heterocyclic units were synthesized by the Wittig and the Knoevenagel reactions of corresponding aromatic dialdehydes and different CH-acids or phosphonium salts. Investigation of the effect of various substituents on the luminescent properties has been presented. The new luminophores could be used as emissive or charge transport layers in organic light emitting diodes (OLEDs).

Highlights

The biaryl axis is the central building block in a very large number of various molecules such as natural and pharmacologically active products,[1] chiral reagents,[2] as the source of chiral phases for chromatography,[3] as inflexible “spacers” between two parts of a molecule,[4, 5] as the basis of liquid crystals[6] and fluorescent layers in organic light emitting diodes (OLEDs).[7]
Different substituted biphenyls very often are used as suitable synthetic intermediates for synthesis heteroaromatic and polycyclic aromatic compounds.[8]
Methyl ester of 4, 4’-biphenyldicarboxylic acid 1 is a very convenient and cheap starting material for synthesis of wide range of various biphenyl derivatives, especially because it can be separated from wastes of DMT manufacture.[9, 10]

Summary

Introduction

The biaryl axis is the central building block in a very large number of various molecules such as natural and pharmacologically active products,[1] chiral reagents,[2] as the source of chiral phases for chromatography,[3] as inflexible “spacers” between two parts of a molecule,[4, 5] as the basis of liquid crystals[6] and fluorescent layers in OLEDs.[7]. The reaction mixture was heated at 75°C, 16.5 g (0.1 mol) of 1-bromohexane was added and the resulting solution was stirred for 10 h at 75°C, was poured into 0.5 l of 5% hydrochloric acid, and extracted with ethyl acetate.

Results

Conclusion