Related Experiment Video
Updated: Jun 21, 2026
08:51
Scale-up Chemical Synthesis of Thermally-activated Delayed Fluorescence Emitters Based on the Dibenzothiophene-S,S-Dioxide Core
Published on: October 24, 2017
Asymmetrical fluorene[2,3-b]benzo[d]thiophene derivatives: synthesis, solid-state structures, and application in
Chunyan Du1, Shanghui Ye, Jianming Chen
1Beijing National Laboratory for Molecular Sciences, Organic Solids Laboratory, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|July 18, 2009
Summary
Novel fluorene[2,3-b]benzo[d]thiophene (FBT) compounds were synthesized, showing tunable fluorescence and stability. These FBT derivatives demonstrate potential for efficient organic light-emitting diodes, with one achieving 91% quantum yield.
Area of Science:
- Organic Chemistry
- Materials Science
- Solid-State Physics
Background:
- Fluorene[2,3-b]benzo[d]thiophene (FBT) derivatives are explored for optoelectronic applications.
- Tuning molecular structure is key to controlling material properties.
Purpose of the Study:
- Synthesize and characterize novel asymmetrical FBT compounds.
- Investigate the impact of substituent side chains on solid-state packing and photophysical properties.
- Evaluate the performance of FBT derivatives in organic light-emitting diodes (OLEDs).
Main Methods:
- Asymmetrical fused compound synthesis.
- Single-crystal X-ray diffraction for structural analysis.
- Density Functional Theory (DFT) calculations.
- Photophysical and electrochemical characterization.
- Fabrication and testing of solution-processed OLED devices.
Main Results:
- Successful synthesis and characterization of novel FBT compounds.
- Side chain length significantly influences solid-state packing.
- FBTs exhibit large band gaps, low-lying HOMO levels, and good oxidative stability.
- Substituents modulate fluorescence properties, with a di-n-hexyl derivative reaching 91% quantum yield.
- Di-n-butyl FBT as a host material in green phosphorescent OLEDs achieved 14,185 cd m⁻² brightness and 12 cd A⁻¹ efficiency.
Conclusions:
- The synthesized FBT compounds offer tunable fluorescence and excellent stability.
- Side chain engineering is a viable strategy for controlling FBT properties.
- FBT derivatives show promise as host materials for high-performance OLEDs.
Related Concept Videos
01:13Electrophilic Aromatic Substitution: Fluorination and Iodination of Benzene
Bromination and chlorination of aromatic rings by electrophilic aromatic substitution reactions are easily achieved, but fluorination and iodination are difficult to achieve. Fluorine is so reactive that its reaction with benzene is difficult to control, resulting in poor yields of monofluoroaromatic products. To address this, Selectfluor reagent is used as a fluorine source in which a fluorine atom is bonded to a positively charged nitrogen.
01:26Variables Affecting Phosphorescence and Fluorescence
Fluorescence and phosphorescence are essential phenomena in fields like analytical chemistry, biological imaging, and materials science, where they detect molecular properties and visualize cellular structures. Understanding the variables that influence these luminescent behaviors is crucial for maximizing accuracy and efficiency in their applications. These variables can broadly be grouped into chemical structure, solvent properties, and external conditions, each playing a distinct role in...
01:16Structure of Conjugated Dienes
Introduction
Conjugated dienes are compounds characterized by the presence of alternating double and single bonds. In a conjugated system like 1,3-butadiene, the unhybridized 2p orbital on each carbon overlaps continuously, allowing the π electrons to be delocalized across the entire molecule. In contrast, this type of overlap does not occur in cumulated and isolated dienes, such as 2,3-pentadiene and 1,4-pentadiene, respectively. Instead, the π electrons remain localized between the double...
Conjugated dienes are compounds characterized by the presence of alternating double and single bonds. In a conjugated system like 1,3-butadiene, the unhybridized 2p orbital on each carbon overlaps continuously, allowing the π electrons to be delocalized across the entire molecule. In contrast, this type of overlap does not occur in cumulated and isolated dienes, such as 2,3-pentadiene and 1,4-pentadiene, respectively. Instead, the π electrons remain localized between the double...
01:17Thermal Electrocyclic Reactions: Stereochemistry
The stereochemistry of electrocyclic reactions is strongly influenced by the orbital symmetry of the polyene HOMO. Under thermal conditions, the reaction proceeds via the ground-state HOMO.
Selection Rules: Thermal Activation
Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.
Selection Rules: Thermal Activation
Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.
01:26Thermal and Photochemical Electrocyclic Reactions: Overview
Electrocyclic reactions are reversible reactions. They involve an intramolecular cyclization or ring-opening of a conjugated polyene. Shown below are two examples of electrocyclic reactions. In the first reaction, the formation of the cyclic product is favored. In contrast, in the second reaction, ring-opening is favored due to the high ring strain associated with cyclobutene formation.
01:28Diels–Alder Reaction Forming Cyclic Products: Stereochemistry
The Diels–Alder reaction is one of the robust methods for synthesizing unsaturated six-membered rings. The reaction involves a concerted cyclic movement of six π electrons: four π electrons from the diene and two π electrons from the dienophile.