4-Bromodibenzothiophene: Properties, Handling & Lab Use Guide

4-Bromodibenzothiophene is a brominated sulfur-containing polycyclic aromatic compound widely used as a versatile building block in palladium-catalyzed cross-coupling reactions, C–H functionalization studies, and the synthesis of organic electronic and OLED materials.

CAS Number

97511-05-2

Molecular Formula

C₁₂H₇BrS

Molecular Weight

263.15 g/mol

Appearance

White to off-white crystalline solid

Recommended Storage

Store at room temperature in a cool, dry, well-ventilated area away from light

Key Application

Palladium-catalyzed cross-coupling reactions and organic semiconductor synthesis

Chemical Identity and Physical Properties

4-Bromodibenzothiophene (CAS 97511-05-2, SKU B152940) is a halogenated derivative of dibenzothiophene, a tricyclic aromatic system in which a sulfur atom bridges two benzene rings. Bromine substitution at the 4-position — adjacent to the sulfur-bearing ring junction — imparts both steric and electronic characteristics that distinguish this compound from other positional isomers.

The compound has the molecular formula C₁₂H₇BrS and a molecular weight of approximately 263.15 g/mol. It is typically supplied as a white to off-white crystalline solid. Its polycyclic aromatic scaffold confers a relatively high melting point and low volatility compared with monocyclic aryl bromides, reducing acute inhalation risk during routine handling; nonetheless, standard laboratory precautions should be observed.

The C–Br bond at the 4-position is activated toward oxidative addition by palladium(0) and other low-valent transition metals, making this compound a reactive partner in a wide range of metal-catalyzed transformations.

Key Research Applications

Palladium-Catalyzed Cross-Coupling: The aryl bromide functionality of 4-Bromodibenzothiophene makes it a suitable electrophilic partner in Suzuki–Miyaura, Buchwald–Hartwig, Negishi, and Kumada coupling reactions. These transformations allow researchers to install diverse aryl, amino, or alkyl groups at the 4-position of the dibenzothiophene core, enabling rapid diversification of the sulfur-heterocycle framework.

Organic Electronics and OLED Materials: Dibenzothiophene-containing architectures are established components of hole-transport layers and emitter host matrices in organic light-emitting diodes (OLEDs). 4-Bromodibenzothiophene serves as a key intermediate for synthesizing such functional materials, with the bromine handle allowing straightforward attachment to larger conjugated systems.

C–H Activation and Directed Functionalization: The well-defined electronic landscape of the dibenzothiophene core makes 4-Bromodibenzothiophene useful in mechanistic studies of transition-metal-catalyzed C–H functionalization, where the sulfur atom can act as a directing or coordinating element.

Medicinal and Agrochemical Scaffolds: Dibenzothiophene motifs appear in pharmacologically active compounds. Brominated intermediates such as this compound can serve as starting points for structure–activity relationship (SAR) studies targeting sulfur-heterocycle-containing drug candidates.

Safe Handling and Storage Guidelines

Personal Protective Equipment (PPE): When handling 4-Bromodibenzothiophene, wear appropriate PPE including nitrile or neoprene gloves, a laboratory coat, and safety glasses or goggles. Work in a well-ventilated fume hood to minimize dust or aerosol inhalation, particularly when weighing quantities of the solid.

Storage: Store the compound at room temperature in a cool, dry, and well-ventilated area, protected from light and moisture. Keep the container tightly sealed when not in use. Segregate from strong oxidizing agents and bases. Under recommended storage conditions, the compound is expected to remain stable for an extended period; always verify the lot-specific certificate of analysis (CoA) for confirmed purity before use.

Waste Disposal: Dispose of residues and contaminated materials in accordance with local, regional, and national regulations governing halogenated organic waste. Do not pour down the drain without verifying compliance with applicable environmental legislation.

First Aid: In case of skin or eye contact, flush immediately with copious water for at least 15 minutes and seek medical advice. If inhaled in significant quantities, move to fresh air and consult a physician.

Practical Tips for Cross-Coupling Reactions

Catalyst Selection: Standard Pd(0) precatalysts such as Pd(PPh₃)₄ or Pd₂(dba)₃ with phosphine ligands (e.g., SPhos, RuPhos) are effective for Suzuki–Miyaura coupling of 4-Bromodibenzothiophene with arylboronic acids. The aryl bromide is generally more reactive than the corresponding aryl chloride but less reactive than an aryl iodide; optimize catalyst loading accordingly.

Solvent and Base: For Suzuki–Miyaura reactions, mixed aqueous–organic solvent systems (e.g., toluene/water, DMF/water, or dioxane/water) with inorganic bases such as K₂CO₃, Cs₂CO₃, or K₃PO₄ are commonly employed. Ensure thorough degassing of solvents to prevent catalyst deactivation by dissolved oxygen.

Reaction Atmosphere: Conduct reactions under an inert atmosphere (nitrogen or argon) to protect the palladium catalyst from oxidative decomposition. Use standard Schlenk technique or a glovebox for air-sensitive catalyst preparations.

Purity Verification: Before beginning a synthesis, confirm the purity of the reagent by consulting the Aladdin Scientific certificate of analysis. Trace impurities in aryl halide reagents can poison catalysts and reduce yields unpredictably.

Quality, Purity and Ordering Information

Aladdin Scientific offers 4-Bromodibenzothiophene (SKU: B152940) with purity confirmed by HPLC and/or GC analysis, as detailed in the lot-specific certificate of analysis available upon request. Researchers should specify required purity grade at the time of ordering to ensure suitability for their intended application — for example, OLED-grade synthesis may require higher purity than general synthetic use.

The product is available in multiple pack sizes to suit both exploratory milligram-scale screening and larger preparative workflows. Contact Aladdin Scientific customer service or visit the product page for current pricing, stock availability, and bulk quotation requests. Custom synthesis inquiries for related dibenzothiophene derivatives can also be directed to our technical sales team.

All shipments are accompanied by a safety data sheet (SDS) and certificate of analysis. Store received material promptly under recommended conditions upon arrival to maintain reagent integrity.

Frequently asked questions

What palladium catalysts are recommended for coupling reactions with 4-Bromodibenzothiophene?

Pd(PPh₃)₄ and Pd₂(dba)₃ combined with bulky phosphine ligands such as SPhos or RuPhos are commonly used for Suzuki–Miyaura and related cross-coupling reactions with aryl bromides. Catalyst loading and ligand choice should be optimized based on the specific coupling partner and desired scale.

How should 4-Bromodibenzothiophene be stored to maintain long-term stability?

Store the compound in a tightly sealed container at room temperature in a cool, dry, well-ventilated area away from direct light and moisture. Under these conditions the crystalline solid is expected to remain stable for an extended period. Always check the lot certificate of analysis for purity before use.

Is 4-Bromodibenzothiophene suitable as an intermediate for OLED material synthesis?

Yes. Dibenzothiophene-based motifs are established in OLED hole-transport and host-emitter material architectures. The bromine substituent at the 4-position provides a reactive handle for palladium-catalyzed coupling with aryl or amine partners, enabling construction of extended conjugated frameworks suitable for organic electronic applications.

What safety precautions should I take when weighing 4-Bromodibenzothiophene?

Weigh the compound inside a well-ventilated fume hood while wearing nitrile gloves, a laboratory coat, and safety glasses to prevent dust inhalation and skin or eye contact. Although the polycyclic solid has low volatility, fine particles generated during handling can pose an inhalation hazard.

Can 4-Bromodibenzothiophene be used in Buchwald–Hartwig amination reactions?

Yes, aryl bromides such as 4-Bromodibenzothiophene are suitable substrates for palladium-catalyzed Buchwald–Hartwig amination. Appropriate ligands such as BINAP, DavePhos, or RuPhos with a palladium source and a suitable base (e.g., Cs₂CO₃ or NaOtBu) are typically employed. Reaction conditions should be optimized for the specific amine coupling partner.

References

1. Miyaura, N.; Suzuki, A. Palladium-Catalyzed Cross-Coupling Reactions of Organoboron Compounds. Chemical Reviews 1995, 95, 2457–2483. doi:10.1021/cr00039a007
2. Hartwig, J. F. Evolution of a Fourth Generation Catalyst for the Amination and Thioetherification of Aryl Halides. Accounts of Chemical Research 2008, 41, 1534–1544. doi:10.1021/ar800098p
3. Shirota, Y.; Kageyama, H. Charge Carrier Transporting Molecular Materials and Their Applications in Devices. Chemical Reviews 2007, 107, 953–1010. doi:10.1021/cr050143+
4. Aladdin Scientific Certificate of Analysis, 4-Bromodibenzothiophene, SKU B152940. Available upon request from Aladdin Scientific.

Products are supplied for research and development use only. Not for use in humans, animals, diagnosis, or therapy.