2-Bromo-9,9'-spirobifluorene
[CAS# 171408-76-7]

Identification

• Classification: Pharmaceutical intermediate >> OLED material intermediate
• Name: 2-Bromo-9,9'-spirobifluorene
• Molecular Formula: C₂₅H₁₅Br
• Molecular Weight: 395.29
• CAS Registry Number: 171408-76-7
• EC Number: 605-609-0
• SMILES: C1=CC=C2C(=C1)C3=C(C24C5=CC=CC=C5C6=CC=CC=C46)C=C(C=C3)Br

Properties

• Melting point: 184 °C

Safety Data

• Hazard Symbols: GHS07 Warning
• Risk Statements: H302
• Safety Statements: P280-P305+P351+P338

Discovery and Applications

2-Bromo-9,9'-spirobifluorene is a significant compound in the field of organic electronics and materials science, recognized for its unique molecular structure and applications in the development of advanced optoelectronic devices. The discovery of 2-bromo-9,9'-spirobifluorene can be traced to research on spirobifluorene derivatives, which are characterized by a spiro-linked fluorene core that provides a rigid, three-dimensional structure. The introduction of a bromine atom at the 2-position of the fluorene ring enhances the compound’s reactivity, making it a valuable building block in the synthesis of more complex organic molecules.

The synthesis of 2-bromo-9,9'-spirobifluorene typically involves the bromination of 9,9'-spirobifluorene, a process that is carried out under controlled conditions to ensure selective substitution at the 2-position. This selective bromination is critical for maintaining the structural integrity of the spirobifluorene core while introducing a reactive site that can participate in various coupling reactions. The resulting compound, with its combination of rigidity and reactivity, serves as an important intermediate in the synthesis of organic semiconductors, light-emitting materials, and other advanced materials.

One of the primary applications of 2-bromo-9,9'-spirobifluorene is in the development of organic light-emitting diodes (OLEDs). The spirobifluorene core provides excellent thermal and morphological stability, which are essential for the long-term performance of OLED devices. Additionally, the presence of the bromine atom allows for further functionalization through cross-coupling reactions, enabling the introduction of various functional groups that can tune the electronic properties of the material. This versatility makes 2-bromo-9,9'-spirobifluorene a key component in the design of high-efficiency, stable OLED materials.

In the field of organic photovoltaics (OPVs), 2-bromo-9,9'-spirobifluorene is used as a precursor in the synthesis of donor and acceptor materials that form the active layer of these devices. The rigid spirobifluorene structure ensures that the resulting materials have a well-defined, stable morphology, which is crucial for efficient charge transport and light absorption in OPVs. By enabling precise control over the molecular structure of the active materials, 2-bromo-9,9'-spirobifluorene contributes to the development of high-performance solar cells with improved efficiency and durability.

The compound is also utilized in the synthesis of organic semiconductors for use in organic field-effect transistors (OFETs). The unique three-dimensional structure of spirobifluorene derivatives provides good charge carrier mobility and stability, which are essential for the operation of OFETs. The bromine atom in 2-bromo-9,9'-spirobifluorene facilitates the introduction of additional functional groups that can modulate the electronic properties of the semiconductor, allowing for the fine-tuning of device performance. This adaptability makes the compound a valuable tool in the development of flexible and wearable electronic devices.

Beyond optoelectronics, 2-bromo-9,9'-spirobifluorene is also explored in materials science for the creation of novel polymers and copolymers. Its rigid structure and reactive bromine site enable the formation of highly cross-linked, stable polymers with desirable mechanical and thermal properties. These materials have potential applications in areas such as coatings, adhesives, and high-performance plastics, where durability and resistance to environmental factors are important.

Research into 2-bromo-9,9'-spirobifluorene continues to expand its potential applications, particularly in the development of new materials for emerging technologies. The compound’s ability to be easily modified and incorporated into larger molecular frameworks ensures its ongoing relevance in the fields of organic electronics, materials science, and beyond. As the demand for advanced materials with specific electronic and mechanical properties grows, 2-bromo-9,9'-spirobifluorene is likely to remain a cornerstone in the design and synthesis of next-generation materials.

References

2019. Hole-transporting material based on spirobifluorene unit with perfect amorphous and high stability for efficient OLEDs. Journal of Materials Science: Materials in Electronics.
DOI: 10.1007/s10854-019-01493-9