Basic Chemical Information: 2-(9,9'-Spirobi[fluorene]-2'-yl)-9,9'-spirobi[fluorene], commonly abbreviated as BSBF, is a high-purity aromatic organic compound with the unique CAS number 664345-18-0. It belongs to the spirobifluorene derivative family, a class of star functional materials widely researched in organic optoelectronic fields. The standard chemical molecular formula of this compound is C₅₀H₃₀, with a precise molecular weight of 630.77 g/mol and an accurate mass of 630.234741. Classified as a pure hydrocarbon and an ortho-linked oligo-spirobifluorene, it is primarily utilized as a host matrix material in advanced phosphorescent organic light-emitting diodes (PhOLEDs) and other optoelectronic devices. Its unique molecular structure provides a combination of high thermal stability, a wide energy bandgap, and excellent morphological properties, making it an essential component for achieving high efficiency and long operational lifetimes in next-generation displays. Physical and Chemical Properties: This spirobifluorene dimer possesses distinctive physical parameters that determine its application advantages in advanced material fields. Its calculated density is 1.4±0.1 g/cm³, and the refractive index reaches 1.832, indicating excellent optical refractive performance suitable for optical device fabrication. The compound has a high LogP value of 12.52, reflecting strong lipophilicity and good solubility in common organic solvents such as toluene, chloroform, and tetrahydrofuran, while it is almost insoluble in water and polar inorganic solvents. In terms of chemical stability, BSBF exhibits outstanding thermal and chemical inertness. The rigid fully conjugated spirocyclic structure endows it with high thermal decomposition temperature, low volatility, and strong resistance to oxidation and photobleaching.
Applications in Organic Electronics: The primary and most critical application of BSBF is as a host material in the emissive layer of blue phosphorescent OLEDs (PhOLEDs). · High Triplet Energy (ET): The rigid, twisted structure of BSBF provides a high triplet energy level. This is crucial for confining the triplet excitons on the blue phosphorescent dopant, thereby preventing energy back-transfer and enabling highly efficient electrophosphorescence. · Suppression of Aggregation: The bulky spiro-structure effectively suppresses aggregation and exciton quenching, which are common issues in planar aromatic hydrocarbons. This property ensures efficient charge balance and stable device performance over time. · Morphological Stability: The high glass transition temperature associated with its rigid structure allows BSBF to form stable, amorphous thin films during thermal evaporation. This morphological stability is essential for the long-term operational integrity of OLEDs under the heat generated during use. Synthetic Method Overview: At present, the mainstream synthesis route of 2-(9,9'-spirobi[fluorene]-2'-yl)-9,9'-spirobi[fluorene] is based on coupling reaction of monosubstituted spirobifluorene monomers. Taking 2-halogenated-9,9'-spirobifluorene as the starting material, target products are efficiently synthesized through palladium-catalyzed Suzuki coupling or Ullmann homocoupling reaction under anhydrous and oxygen-free inert atmosphere. The synthesis process features mild reaction conditions, high reaction selectivity, and easy separation and purification of products. After the reaction is completed, high-purity products (≥98%) can be obtained by recrystallization, column chromatography and vacuum sublimation purification. The mature synthetic route realizes controllable mass production of the compound, which can meet the demand of laboratory scientific research and industrial batch preparation of optoelectronic materials. Research and Development Prospects: With the rapid development of flexible optoelectronic devices and high-efficiency organic photoelectric materials, spirobifluorene derivatives represented by CAS 664345-18-0 have become a research hotspot in material chemistry. Its unique spirobifluorene architecture imparts essential characteristics—high thermal stability, a wide bandgap, and morphological robustness—that are fundamental for developing efficient, bright, and durable displays. As research into organic semiconductors continues to evolve, BSBF stands as a benchmark material for stable and efficient host matrices. Product manager: Joy Wu CONTACT/Email: Joy@coreychem.com
