1. Product Overview
2-Bromo-9,9-diphenyl-9H-fluorene (CAS 474918-32-6) is a key brominated fluorene derivative with the molecular formula C₂₅H₁₇Br and a molecular weight of 397.31. This compound features a rigid, planar fluorene core at the 9-position of which two phenyl groups are attached, creating a bulky, non-planar 9,9-diphenylfluorene scaffold that is widely recognized in organic electronics. The bromine atom is selectively positioned at the 2-position of the fluorene ring, serving as an excellent leaving group for palladium-catalyzed cross-coupling reactions such as Suzuki, Stille, and Heck couplings. It typically presents as an off-white to almost white solid or crystalline powder with a high melting point of 217–221 °C. Supplied at a minimum purity of 98%, it is primarily utilized as a high-performance OLED intermediate for synthesizing hole-transporting materials (HTLs), host materials, and emitters, as well as a fine chemical intermediate in pharmaceutical and advanced material research.
2. Key Features and Advantages
• High Purity Standard: Minimum 98% assay (GC/HPLC) ensures clean cross-coupling profiles and high device yields in OLED fabrication.
• Strategic Bromine Handle: The 2-bromo substituent enables regioselective functionalization via standard Pd-catalyzed reactions, allowing precise introduction of aryl, heteroaryl, or alkenyl groups.
• Steric and Electronic Design: The 9,9-diphenyl groups suppress molecular aggregation (preventing concentration quenching) and elevate the triplet energy level, which is critical for blue-phosphorescent OLED hosts.
• Excellent Thermal Stability: High melting point (217–221 °C) and robust spiro/fluorene framework support vacuum thermal evaporation (VTE) and solution processing.
• Optimal Morphology: Supplied as a free-flowing off-white solid, facilitating accurate weighing for both lab-scale synthesis and pilot-scale material production.
• Dual Utility: Bridges OLED material science (charge transport) and fine chemical/pharmaceutical intermediate applications (rigid biphenyl-like scaffold).
3. Main Applications
• OLED Intermediates: A fundamental building block for synthesizing 2-substituted-9,9-diphenylfluorene derivatives used as hole-transporting layers (HTL), electron-blocking layers (EBL), and host materials in phosphorescent and TADF OLEDs. Commonly coupled with carbazole, triphenylamine, or triazine moieties.
• Organic Semiconductors: Incorporated into the backbone of organic thin-film transistors (OTFTs) and organic photovoltaics (OPVs) to enhance charge carrier mobility and thermal stability.
• Pharmaceutical Fine Chemical: The fluorene scaffold is occasionally used in medicinal chemistry as a rigid, lipophilic core for designing enzyme inhibitors and CNS-active compounds; also serves as a precursor for fluorescent probes.
• Custom Material Synthesis: Acts as a versatile electrophilic synthon for introducing the C₂₅H₁₆PhBr fragment into larger π-conjugated systems via Suzuki–Miyaura cross-coupling.
• Polymer Chemistry: Used as a monomer or chain-end capping agent in the synthesis of conjugated polymers and polyfluorenes for optoelectronic devices.
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); for long-term storage, keep in a desiccator or refrigerate at 2–8 °C to maintain optimal purity and prevent slow oxidation or discoloration. The solid is stable under normal conditions but should be kept away from strong bases and strong reducing agents that could promote dehalogenation. Handle in a fume hood or well-ventilated workspace; wear nitrile gloves, safety goggles, and a lab coat. Minimize dust generation during transfer. Reseal immediately after use. Do not store with incompatible chemicals such as finely divided metals or strong oxidizers. Dispose of as halogenated organic waste per local regulations. Always refer to the latest SDS.
6. Safety Overview
This substance may cause irritation to the skin, eyes, and respiratory tract. Signal Word: Warning. Hazard Statements: H315 - Causes skin irritation; H319 - Causes serious eye irritation; H335 - May cause respiratory irritation; H413 - May cause long-lasting harmful effects to aquatic life. Precautionary Statements: P261 - Avoid breathing dust/fume/mist; P264 - Wash thoroughly with soap and water after handling; P271 - Use only outdoors or in a well-ventilated area; P273 - Avoid release to the environment; P280 - Wear protective gloves/protective clothing/eye protection/face protection; 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 and easy to do; continue rinsing; P312 - Call a poison center/doctor if you feel unwell; 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/regional/national regulations for halogenated aromatic compounds. In case of contact, rinse affected area with copious water; for eye contact flush ≥15 min and seek medical attention if irritation persists.
