2-Bromodibenzothiophene: Handling, Storage & Use Protocol

2-Bromodibenzothiophene is a brominated polycyclic sulfur heterocycle widely employed as a key aryl bromide building block in palladium-catalyzed cross-coupling reactions and the synthesis of advanced organic electronic materials.

CAS Number

Verify with product datasheet (review flag: CAS not provided in source material)

Molecular Formula

C₁₂H₇BrS

Molecular Weight

Approximately 263.15 g/mol (review flag: verify against datasheet)

Appearance

White to off-white crystalline solid (review flag: verify against datasheet)

Storage Condition

Store in a cool, dry, well-ventilated area away from light; seal tightly after use

SKU

B121514

Overview and Chemical Properties

2-Bromodibenzothiophene (SKU: B121514) is an aryl bromide derivative of dibenzothiophene, a tricyclic aromatic sulfur heterocycle. The bromine substituent at the 2-position activates this molecule as a versatile electrophilic partner in metal-catalyzed coupling chemistry. Its rigid planar scaffold and sulfur-containing ring system make it valuable both as a synthetic intermediate and as a precursor to conjugated organic materials used in optoelectronics and organic semiconductors.

The compound is a stable solid under ambient conditions when stored properly, exhibiting characteristic aromatic absorption in UV spectroscopy. Researchers should consult the product certificate of analysis for confirmed purity, melting point, and spectral data prior to use.

Safety and Handling Precautions

Although 2-Bromodibenzothiophene is considered a relatively stable aromatic solid, general precautions for organobromine compounds must be followed:

• Personal Protective Equipment (PPE): Wear chemical-splash goggles, a laboratory coat, and nitrile gloves at all times when handling this compound.
• Ventilation: Handle in a fume hood to avoid inhalation of dust or vapors.
• Skin and Eye Contact: In case of contact, flush immediately with copious amounts of water and seek medical attention if irritation persists.
• Ingestion/Inhalation: Do not eat, drink, or apply cosmetics in the laboratory. If inhaled, move to fresh air immediately.
• Waste Disposal: Dispose of waste in accordance with local, regional, and national environmental regulations for halogenated organic compounds.

Review flag: Full GHS hazard classification and H/P statements should be verified against the current Safety Data Sheet (SDS) for B121514 before use.

Storage Protocol

Proper storage of 2-Bromodibenzothiophene is essential to maintain reagent integrity over time:

1. Temperature: Store at room temperature (15–25 °C) or as specified on the product datasheet. Refrigeration may be advisable for long-term storage; verify with the product SDS.
2. Container: Keep in the original, tightly sealed container to prevent moisture ingress and oxidative degradation.
3. Light: Store away from direct sunlight and UV sources, as aromatic bromides can be sensitive to photolytic degradation.
4. Atmosphere: If the product is moisture-sensitive, consider storing under inert atmosphere (nitrogen or argon) after opening.
5. Segregation: Store away from strong oxidizers, bases, and reactive metals.

Review flag: Specific recommended storage temperature and shelf life should be confirmed from the official B121514 product datasheet or SDS.

Representative Laboratory Use: Palladium-Catalyzed Cross-Coupling

2-Bromodibenzothiophene serves as the aryl halide partner in a variety of transition-metal-catalyzed reactions. The following general protocol outlines its use in a Suzuki–Miyaura cross-coupling reaction as a representative example:

Materials Required

• 2-Bromodibenzothiophene (B121514), 1.0 equiv.
• Arylboronic acid, 1.2–1.5 equiv.
• Pd catalyst (e.g., Pd(PPh₃)₄ or Pd(dppf)Cl₂), 2–5 mol%
• Base (e.g., K₂CO₃ or Cs₂CO₃), 2.0–3.0 equiv.
• Solvent: DMF/water, dioxane/water, or toluene/ethanol (review flag: optimize solvent system for specific substrate)
• Inert atmosphere (N₂ or Ar)

General Procedure

1. Charge a dry Schlenk flask or sealed tube with 2-bromodibenzothiophene, the boronic acid partner, and the palladium catalyst.
2. Add the base and the solvent mixture under an inert atmosphere.
3. Heat the reaction mixture at 80–110 °C with stirring for 12–24 hours (optimize time and temperature for each substrate).
4. Allow the reaction to cool to room temperature, then dilute with ethyl acetate and wash with water and brine.
5. Dry the organic layer over anhydrous MgSO₄ or Na₂SO₄, filter, and concentrate under reduced pressure.
6. Purify the crude product by column chromatography or recrystallization.

Review flag: Reaction conditions above are based on general textbook protocols for Suzuki–Miyaura coupling with aryl bromides. Specific yields, temperatures, and catalyst loadings for 2-bromodibenzothiophene substrates should be verified against primary literature.

Quality Control and Analytical Verification

Before and after use, analysts should confirm the identity and purity of 2-Bromodibenzothiophene using the following standard analytical techniques:

• TLC: Run a thin-layer chromatography check against a reference standard to confirm identity and assess purity before committing material to a reaction.
• ¹H NMR Spectroscopy: Confirm the aromatic proton pattern consistent with the 2-substituted dibenzothiophene scaffold (review flag: reference spectrum should be obtained from literature or the supplier datasheet).
• GC or HPLC: Quantitative purity assessment by gas chromatography or reverse-phase HPLC; compare against the certificate of analysis supplied with product B121514.
• Mass Spectrometry: Confirm molecular ion consistent with C₁₂H₇BrS (review flag: verify exact m/z from datasheet).
• Melting Point: Determine melting point and compare to the value specified on the product datasheet to verify integrity of the solid-state material.

Frequently asked questions

What reactions is 2-Bromodibenzothiophene typically used for?

2-Bromodibenzothiophene is primarily used as an aryl bromide electrophile in palladium-catalyzed cross-coupling reactions such as Suzuki–Miyaura, Negishi, Buchwald–Hartwig, and Stille couplings. It is also employed in the synthesis of conjugated materials for organic electronics and optoelectronic devices.

How should 2-Bromodibenzothiophene be stored to maintain its stability?

The compound should be stored in a tightly sealed container in a cool, dry, and well-ventilated area away from direct light and heat sources. For long-term storage, keeping the material under an inert atmosphere (nitrogen or argon) is recommended. Always consult the product SDS and datasheet for specific storage requirements for lot B121514.

Is 2-Bromodibenzothiophene air- or moisture-sensitive?

As a stable aromatic solid, 2-Bromodibenzothiophene is not expected to be highly sensitive to air or moisture under typical laboratory conditions. However, best practice dictates sealing the container after each use and considering inert-atmosphere storage after opening to prevent any long-term degradation. Confirm specific sensitivity data on the product SDS.

What is the molecular formula and approximate molecular weight of 2-Bromodibenzothiophene?

The molecular formula is C₁₂H₇BrS, corresponding to an approximate molecular weight of 263.15 g/mol. Researchers should verify the exact molecular weight and CAS number against the certificate of analysis provided with SKU B121514.

Can 2-Bromodibenzothiophene be used in C–H activation or direct arylation reactions?

In principle, aryl bromides such as 2-bromodibenzothiophene can serve as coupling partners in transition-metal-catalyzed C–H functionalization and direct arylation protocols. The specific applicability depends on the catalyst system and substrate compatibility. Consult primary literature for validated conditions before use.

References

1. Miyaura, N.; Suzuki, A. Palladium-Catalyzed Cross-Coupling Reactions of Organoboron Compounds. Chemical Reviews 1995, 95 (7), 2457–2483. doi:10.1021/cr00039a007
2. Joule, J. A.; Mills, K. Heterocyclic Chemistry, 5th ed.; Wiley-Blackwell: Oxford, 2010.
3. Aladdin Scientific. Product Datasheet: 2-Bromodibenzothiophene, SKU B121514. Retrieved from Aladdin Scientific product catalog.

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