4,4''-Dibromo-p-terphenyl CAS 17788-94-2 97% Off White to Light Yellow Solid OLED Intermediate Fine Chemical Intermediate

1. Product Overview

4,4''-Dibromo-p-terphenyl (CAS 17788-94-2) is a para-terphenyl derivative with the molecular formula C₁₈H₁₂Br₂ and a molecular weight of 388.10. Also known as 4,4''-Dibromo-1,1':4',1''-terphenyl or DBTP, it consists of three linearly connected benzene rings with bromine atoms at both terminal 4- and 4''-positions. This rigid, fully conjugated linear oligoarene typically appears as an off-white to light yellow crystalline solid or powder, with a high melting point of approximately 315 °C. The two terminal bromine substituents serve as excellent handles for palladium-catalyzed cross-coupling reactions (Suzuki, Stille, Yamamoto), enabling the stepwise or symmetric elongation of π-conjugated systems. Supplied at ≥97% purity (GC/HPLC), it is a key OLED intermediate for synthesizing host/emitter materials and liquid crystals, as well as a fine chemical building block for advanced organic semiconductors and terphenyl-based scaffolds.

2. Key Features and Advantages

• High Purity Standard: Minimum 97% by GC/HPLC ensures clean coupling profiles and minimal byproducts in sensitive OLED material syntheses.

• Dual Reactive Bromine Sites: Terminal 4,4''-dibromo configuration allows symmetric or sequential Suzuki/Stille couplings to build extended π-systems, star-shaped oligomers, and polymeric backbones.

• Rigid Linear Conjugated Core: The p-terphenyl skeleton provides excellent planarity, strong π–π stacking, and high thermal stability (mp ~315 °C), ideal for charge-transport layers and vacuum deposition.

• Distinctive Morphology: Supplied as off-white to light yellow solid/crystals, facilitating accurate weighing and handling in lab and pilot scales.

• Broad Synthetic Utility: Serves as a versatile electrophilic synthon for introducing the C₁₈H₁₀Br₂ fragment; also reducible to diamine or used in Yamamoto coupling for poly(p-phenylene).

• Consistent Batch Quality: Each lot includes CoA (GC/HPLC, mp, NMR on request), suitable for OLED R&D, liquid crystal development, and fine chemical intermediate workflows.

3. Main Applications

• OLED Intermediates: A fundamental building block for constructing hole-transporting materials (HTL), host materials, and emissive layers. Terminal bromines are coupled with carbazole, triphenylamine, fluorene, or triazine moieties to tune HOMO/LUMO levels and triplet energies for phosphorescent/TADF OLEDs.

• Liquid Crystal Materials: Used in synthesizing biphenyl/terphenyl-based liquid crystals for display technologies, leveraging the linear rigid core and thermal stability.

• Organic Semiconductors: Incorporated into organic thin-film transistors (OTFTs), organic photovoltaics (OPVs), and covalent organic frameworks (COFs) as a linear dibromo linker.

• Fine Chemical Synthesis: Acts as a precursor for terphenyl-derived ligands, macrocycles, and pharmaceutical research scaffolds (terphenyl motif shows immunomodulatory/neuroprotective bioactivity in literature).

• Polymer Chemistry: Employed in Yamamoto or Suzuki polycondensation to produce poly(p-phenylene) derivatives and conjugated microporous polymers (CMPs) for gas storage and optoelectronics.

4. Technical Specifications

5. Storage and Handling

Store in a tightly sealed container in a cool, dry, and well-ventilated area protected from light. Stable at room temperature (15–25 °C) but best kept in a desiccator or refrigerator (2–8 °C or <15 °C) to maintain color and purity over long term; the high melting point solid is not moisture-sensitive but can slowly discolor upon prolonged light exposure. Handle in a fume hood or well-ventilated workspace; wear nitrile gloves, safety goggles, and a lab coat. Minimize dust generation during transfer. Avoid contact with strong bases, strong reducing agents (risk of debromination), and finely divided metals. Reseal immediately after use; consider inert gas purge for opened packages. Incompatible with strong oxidizers. Dispose as halogenated aromatic organic waste per local regulations. Always refer to the latest SDS.

6. Safety Overview

This substance is classified as an irritant with potential aquatic hazard. Signal Word: Warning. Hazard Statements: H302—Harmful if swallowed; H315—Causes skin irritation; H319—Causes serious eye irritation; H335—May cause respiratory irritation; H410—Very toxic to aquatic life with long-lasting effects. Precautionary Statements: P261—Avoid breathing dust/fume/mist; P264—Wash thoroughly after handling; P270—Do not eat, drink or smoke when using; P271—Use only outdoors or in well-ventilated area; P273—Avoid release to the environment; P280—Wear protective gloves/eye protection/face protection; P301+P312—IF SWALLOWED: Call a poison center/doctor if you feel unwell; P302+P352—IF ON SKIN: Wash with plenty of soap and water; P305+P351+P338—IF IN EYES: Rinse cautiously with water for several minutes, remove contact lenses if present, continue rinsing; P330—Rinse mouth; P332+P313—If skin irritation occurs: Get medical advice/attention; P337+P313—If eye irritation persists: Get medical advice/attention; P362—Take off contaminated clothing and wash before reuse; P403+P233—Store in a well-ventilated place, keep container tightly closed; P501—Dispose of contents/container in accordance with local regulations for halogenated aromatic compounds. In case of contact, rinse affected skin/eyes with copious water; for ingestion rinse mouth and seek medical advice if unwell. Not classified as explosive; contains bromine—avoid strong reducers/high heat. Always use latest SDS.