For chemists and material scientists engaged in advanced synthesis, understanding the fundamental properties and reactivity of key building blocks is crucial. 1,3-Dibromo-5-iodobenzene (CAS 19752-57-9) is one such compound, prized for its unique structure and the versatile chemical transformations it enables. This article provides an overview of its properties and reactivity, essential knowledge for anyone looking to buy 1,3-dibromo-5-iodobenzene.

Physicochemical Properties: The Foundation of Utility

1,3-Dibromo-5-iodobenzene is characterized by its aromatic benzene core substituted with three halogen atoms: two bromine atoms and one iodine atom. These substituents are strategically positioned at the 1, 3, and 5 positions of the benzene ring. This specific arrangement influences its physical and chemical behavior. Key properties include:

  • Molecular Formula: C6H3Br2I
  • Molecular Weight: Approximately 361.801 g/mol. This relatively high molecular weight is due to the presence of heavy halogen atoms.
  • Appearance: Typically supplied as a light yellow to brown crystalline powder or solid. The exact color can depend on the purity and specific processing.
  • Melting Point (MP): While not always explicitly stated in basic product listings, it exists as a solid at room temperature. Precise MP data is critical for certain applications and is usually provided on detailed specification sheets.
  • Boiling Point (BP): Recorded at around 302.7±32.0 °C at 760 mmHg. This high boiling point indicates its low volatility at standard conditions.
  • Solubility: Generally insoluble in water but soluble in common organic solvents such as dichloromethane, acetone, and ethyl acetate.
  • Purity: High purity grades, such as 97% min or higher, are commonly available from reputable manufacturers like NINGBO INNO PHARMCHEM CO.,LTD., ensuring its suitability for demanding applications.

Chemical Reactivity: A Gateway to Complex Molecules

The true value of 1,3-Dibromo-5-iodobenzene lies in its versatile chemical reactivity, primarily stemming from the three carbon-halogen bonds. The differing electronegativities and bond strengths of the C-Br and C-I bonds allow for regioselective transformations, enabling chemists to perform sequential reactions.

  • Cross-Coupling Reactions: This is perhaps its most significant area of application. The compound readily participates in palladium-catalyzed cross-coupling reactions:
    • Suzuki-Miyaura Coupling: Reacting with organoboron compounds to form new carbon-carbon bonds. The C-I bond is typically more reactive than the C-Br bonds, allowing for selective coupling at the iodine position first.
    • Sonogashira Coupling: Coupling with terminal alkynes to form carbon-carbon triple bonds. Again, selective coupling at the iodine position is often achievable.
    • Buchwald-Hartwig Amination: Forming carbon-nitrogen bonds by reacting with amines.
    • Stille Coupling: Reacting with organotin compounds.
  • Lithiation and Grignard Reactions: The carbon-halogen bonds can undergo halogen-metal exchange reactions (e.g., with n-butyllithium or Grignard reagents) to form organometallic intermediates, which can then be reacted with electrophiles. Selective lithiation can often be achieved, prioritizing the more reactive C-I bond.
  • Nucleophilic Aromatic Substitution: While less common for aryl halides, under specific conditions, nucleophilic substitution can occur.

The ability to selectively functionalize each halogen position makes 1,3-Dibromo-5-iodobenzene an indispensable building block for synthesizing complex polyaromatic systems, functional dyes, pharmaceutical intermediates, and advanced materials for organic electronics. When procurement managers and R&D scientists seek to purchase 1,3-dibromo-5-iodobenzene, they are seeking a key to unlock sophisticated synthetic pathways. Partnering with a reliable chemical intermediate supplier in China ensures access to this versatile molecule with the required purity and consistency.