1,9-Dibromononane
[CAS# 4549-33-1]

Identification

• Classification: Chemical reagent >> Organic reagent >> Halogenated aliphatic hydrocarbon
• Name: 1,9-Dibromononane
• Molecular Formula: C₉H₁₈Br₂
• Molecular Weight: 286.05
• CAS Registry Number: 4549-33-1
• EC Number: 224-913-0
• SMILES: C(CCCCBr)CCCCBr

Properties

• Density: 1.4±0.1 g/cm³ Calc.^*, 1.41 g/mL (Expl.)
• Melting point: -2 °C (Expl.)
• Boiling point: 286.5 °C 760 mmHg (Calc.)^*, 285 - 288 °C (Expl.)
• Flash point: 139.0±17.7 °C (Calc.)^*
• Index of refraction: 1.494 (Calc.)^*, 1.496 (Expl.)

^* Calculated using Advanced Chemistry Development (ACD/Labs) Software.

Safety Data

• Hazard Symbols: GHS07 Warning
• Risk Statements: H315-H319-H335
• Safety Statements: P261-P264-P264+P265-P271-P280-P302+P352-P304+P340-P305+P351+P338-P319-P321-P332+P317-P337+P317-P362+P364-P403+P233-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Eye irritation	Eye Irrit.	2	H319
Skin irritation	Skin Irrit.	2	H315
Specific target organ toxicity - single exposure	STOT SE	3	H335

Discovery and Applications

1,9-Dibromononane is an organic compound consisting of a nine-carbon linear alkyl chain with bromine atoms attached at both terminal carbons. Its molecular formula is C₉H₁₈Br₂, classifying it as an α,ω-dihaloalkane, specifically a dibromo derivative of nonane. The presence of bromine atoms at both ends of the molecule imparts significant chemical reactivity, making 1,9-dibromononane a useful intermediate in organic synthesis and materials science.

The compound is commonly synthesized by the bromination of 1,9-nonanediol, wherein the terminal hydroxyl groups are converted to bromides using reagents such as phosphorus tribromide (PBr₃) or hydrobromic acid under controlled conditions to ensure selective substitution. Alternative synthetic routes include halogenation of terminal alkenes or nucleophilic substitution reactions starting from other functionalized nonane derivatives.

1,9-Dibromononane’s bifunctional bromide groups allow it to readily participate in nucleophilic substitution reactions, facilitating the introduction of a wide variety of nucleophiles such as amines, thiols, azides, and cyanides. This bifunctionality makes it valuable as a difunctional alkylating agent in the synthesis of macrocycles, polymers, and cross-linked materials.

In macrocyclic chemistry, intramolecular nucleophilic substitution involving 1,9-dibromononane can lead to the formation of nine-membered ring compounds. These macrocycles are important in supramolecular chemistry, molecular recognition, and serve as scaffolds in pharmaceutical research.

In polymer science, 1,9-dibromononane acts as a chain extender or cross-linker. Its reaction with bifunctional nucleophiles such as diamines or dithiols produces polyamides, polythioethers, and other polymers. The nine-carbon alkyl spacer contributes flexibility, hydrophobicity, and thermal stability to the polymer backbone, influencing mechanical and physical properties.

The compound also finds applications in materials science for surface functionalization and nanostructure engineering. Its bifunctional nature permits covalent bonding to substrates, modifying surface characteristics such as adhesion, wettability, and molecular arrangement. These properties are valuable in coatings, adhesives, and nanotechnology.

Physically, 1,9-dibromononane is typically a colorless to pale yellow liquid or low-melting solid. It has limited solubility in water but dissolves readily in organic solvents such as ethers, alcohols, and chlorinated hydrocarbons. The bromine atoms increase the molecular weight, boiling point, and density compared to non-halogenated nonane.

Handling requires caution due to potential alkylating activity and irritant effects. The compound is sensitive to light and heat, which may induce decomposition or elimination reactions, and should be stored in cool, dry, and dark conditions.

While 1,9-dibromononane is not pharmacologically active itself, its derivatives are employed in medicinal chemistry for linker synthesis and molecular scaffold design. Its bifunctional bromide groups facilitate conjugation reactions important in drug delivery and biomaterials.

In summary, 1,9-dibromononane is a versatile bifunctional intermediate widely used in organic synthesis, polymer chemistry, and materials science. Its reactive bromine termini and flexible alkyl chain enable diverse chemical transformations and functional applications across various scientific and industrial fields.

References

2023. Synthesis of covalent organic pillars as molecular nanotubes with precise length, diameter and chirality. Nature Synthesis, 2(3).
DOI: 10.1038/s44160-022-00235-w

2022. Low-melting point eutectic mixture of two bismaleimides containing polymethylene flexible and aramide-arylate mesogen groups. Journal of Polymer Research, 29(1).
DOI: 10.1007/s10965-021-02883-6

2012. 1-Phenoxyalkyl-4-[(N,N-disubstitutedamino)alkyl]piperazine derivatives as non-imidazole histamine H3-antagonists. Medicinal Chemistry Research, 21(6).
DOI: 10.1007/s00044-012-0090-2