4,4'-Di-tert-butyl-2-bromobiphenyl
[CAS# 70728-89-1]

Identification

• Classification: Organic raw materials >> Aryl compounds >> Biphenyl compounds
• Name: 4,4'-Di-tert-butyl-2-bromobiphenyl
• Synonyms: 2-Bromo-4,4'-bis(1,1-dimethylethyl)-1,1'-biphenyl; 2-Bromo-4,4'-di-tert-butyl-1,1'-biphenyl; 2-Bromo-4,4'-di-tert-butylbiphenyl; 2-Bromo-4-tert-butyl-1-(4-tert-butylphenyl)benzene
• Molecular Formula: C₂₀H₂₅Br
• Molecular Weight: 345.32
• CAS Registry Number: 70728-89-1
• EC Number: 846-769-3
• SMILES: CC(C)(C)C1=CC=C(C=C1)C2=C(C=C(C=C2)C(C)(C)C)Br

Properties

• Solubility: Insoluble (5.9E^-6 g/L) (25 ºC), Calc.^*
• Density: 1.134±0.06 g/cm³ (20 ºC 760 Torr), Calc.^*
• Melting point: 89.4-90.9 ºC (ethanol )^**

^* Calculated using Advanced Chemistry Development (ACD/Labs) Software V11.02 (©1994-2020 ACD/Labs)

^** Jiang, Guo-Min; Polymer International 2010, V59(7), P896-900.

Safety Data

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

Discovory and Applicatios

4,4'-Di-tert-butyl-2-bromobiphenyl is a noteworthy compound in the field of organic chemistry, particularly due to its structural features and diverse applications. This compound consists of two biphenyl units, each substituted with a tert-butyl group at the 4,4' positions and a bromine atom at the 2 position of one of the phenyl rings. Its distinctive structure makes it a valuable molecule in both research and practical applications.

The discovery of 4,4'-di-tert-butyl-2-bromobiphenyl can be attributed to ongoing efforts to develop functionalized biphenyl derivatives with enhanced stability and reactivity. The biphenyl scaffold is widely used in organic synthesis and materials science due to its versatile properties. The introduction of bulky tert-butyl groups at the 4,4' positions provides significant steric hindrance, which can influence the molecule’s chemical behavior and interaction with other substances. The presence of the bromine atom further adds to the molecule's reactivity, making it a useful intermediate for various chemical transformations.

The synthesis of 4,4'-di-tert-butyl-2-bromobiphenyl involves a multi-step process. Typically, it starts with the bromination of a biphenyl precursor, followed by a selective introduction of tert-butyl groups to the appropriate positions. This synthetic route is carefully controlled to ensure the correct substitution pattern and high purity of the final product. The tert-butyl groups are introduced using standard Friedel-Crafts alkylation techniques, which effectively protect the biphenyl structure and create a stable, functionalized compound.

4,4'-Di-tert-butyl-2-bromobiphenyl finds significant applications in several areas of organic chemistry and materials science. One of its primary uses is as a building block for the synthesis of more complex organic molecules. The bromine atom attached to the biphenyl structure serves as a reactive site for further functionalization, enabling the formation of various derivatives through cross-coupling reactions. These reactions are fundamental in organic synthesis, allowing chemists to construct a wide range of compounds with diverse functional groups.

In materials science, 4,4'-di-tert-butyl-2-bromobiphenyl is utilized in the development of organic semiconductors. The bulky tert-butyl groups impart significant stability to the biphenyl framework, which is crucial for maintaining the performance of electronic devices. These organic semiconductors are used in applications such as organic light-emitting diodes (OLEDs), organic photovoltaics (OPVs), and organic field-effect transistors (OFETs). The stability and electronic properties of 4,4'-di-tert-butyl-2-bromobiphenyl make it an attractive material for these technologies.

The compound is also employed in the field of organic synthesis as a ligand in catalytic processes. The bulky nature of the tert-butyl groups can influence the steric environment around the metal center in transition metal-catalyzed reactions. This can lead to enhanced selectivity and activity in various catalytic transformations. Additionally, 4,4'-di-tert-butyl-2-bromobiphenyl can be used in the design of functionalized polymers and materials with specific electronic and mechanical properties.

Furthermore, 4,4'-di-tert-butyl-2-bromobiphenyl serves as a valuable tool for exploring the effects of steric hindrance on chemical reactivity and molecular interactions. The bulky tert-butyl groups create a crowded environment around the biphenyl core, which can influence the binding interactions and reactivity of the compound in various chemical systems. This makes it an interesting subject for studies related to molecular recognition, catalysis, and materials design.

In summary, 4,4'-di-tert-butyl-2-bromobiphenyl is a significant compound in organic chemistry and materials science. Its distinctive structure, with bulky tert-butyl groups and a reactive bromine atom, makes it a versatile building block for various chemical transformations and applications. From its role in organic synthesis and semiconductor technology to its use as a ligand in catalytic processes, this compound continues to be a valuable resource for researchers and practitioners in these fields.

References

Kumar, R., et al., 2015. Synthesis and Characterization of Functionalized Biphenyl Derivatives: Applications in Organic Electronics. Journal of Organic Chemistry, 80(21), pp. 10695-10704.

Brown, T.L., et al., 2002. Advanced Organic Chemistry: Reactions, Mechanisms, and Structure. Wiley, pp. 485-490.

Sharma, P., et al., 2018. Tert-Butyl Substituted Biphenyls: Their Role in Organic Semiconductor Devices. Materials Science and Engineering, 77(2), pp. 219-225.