8-Bromonaphthalen-1-amine: Properties, Handling & Lab Use Guide

8-Bromonaphthalen-1-amine is a peri-substituted naphthalene building block bearing both a primary arylamine and an aryl bromide functional group, making it a versatile intermediate for cross-coupling reactions, heterocyclic synthesis, and the preparation of luminescent or pharmacologically active compounds.

Chemical Name

8-Bromonaphthalen-1-amine

Molecular Formula

C10H8BrN

Molecular Weight

222.08 g/mol

CAS Number

19819-98-8

Key Functional Groups

Primary arylamine (–NH2) and aryl bromide (C–Br) in peri positions (1,8)

Recommended Storage

Cool, dry, well-ventilated location; protect from moisture and light

Primary Applications

Pd-catalyzed cross-coupling, heterocyclic synthesis, fluorescent material intermediates

Chemical Identity and Physical Properties

8-Bromonaphthalen-1-amine (CAS 19819-98-8; also known as 8-bromo-1-naphthylamine) has the molecular formula C₁₀H₈BrN and a molecular weight of approximately 222.08 g/mol. The compound features a naphthalene ring system with a primary amino group (–NH₂) at the 1-position and a bromine substituent at the 8-position. Because positions 1 and 8 on naphthalene are in close spatial proximity (the peri relationship), these two groups experience significant steric interaction, which influences the compound's conformational behaviour and reactivity.

The molecule is typically obtained as a solid at room temperature. As an arylamine, it is expected to be sparingly soluble in water but soluble in common organic solvents such as dichloromethane, tetrahydrofuran, ethyl acetate, and dimethylformamide. The presence of both a nucleophilic amine and an electrophilic aryl bromide within the same molecule enables a broad range of orthogonal synthetic transformations.

Synthetic Applications and Reactivity

The aryl bromide moiety in 8-Bromonaphthalen-1-amine is well-suited for palladium-catalyzed cross-coupling reactions, including Suzuki–Miyaura, Buchwald–Hartwig amination, Heck, and Sonogashira couplings. These transformations allow straightforward introduction of aryl, alkenyl, alkyl, or alkynyl groups at the 8-position, providing access to a diverse library of 1,8-disubstituted naphthalene derivatives.

The primary amine group offers additional versatility: it can be acylated, sulfonylated, or condensed with carbonyl-containing partners to construct amides, imines, or cyclic heterocycles. The spatial proximity of the amine and bromide in the peri arrangement is particularly useful for constructing five- and six-membered nitrogen-containing rings through intramolecular cyclisation strategies.

Researchers have exploited 1,8-diaminonaphthalene and related peri-substituted naphthalene scaffolds for the preparation of fluorescent sensors, OLED materials, and ligands in coordination chemistry. 8-Bromonaphthalen-1-amine represents a key differentially functionalised precursor in these fields, enabling selective modification at either the amine or bromide site.

Safe Handling and Storage Guidelines

Personal Protective Equipment (PPE): Always wear appropriate PPE when working with 8-Bromonaphthalen-1-amine, including chemical-resistant gloves, a laboratory coat, and safety goggles. As an arylamine compound, it should be treated as a potential irritant and handled in a certified fume hood to minimise inhalation exposure.

Storage: Store the reagent in a tightly sealed container in a cool (2–8 °C or room temperature as specified on the product label), dry, and well-ventilated area away from strong oxidisers, acids, and light. Stability data for this specific compound should be confirmed from the Certificate of Analysis (CoA) supplied with each lot.

Waste Disposal: Dispose of all waste in accordance with local, national, and institutional regulations governing halogenated organic compounds and aromatic amines. Consult the Safety Data Sheet (SDS) for complete hazard classification and first-aid information before use.

Incompatibilities: Avoid contact with strong oxidising agents, strong acids, and reactive acyl halides unless deliberate reaction is intended under controlled conditions.

Quality, Purity and Verification

For synthetic applications where regioselectivity is critical, it is important to verify the identity and purity of 8-Bromonaphthalen-1-amine before use. Recommended analytical techniques include:

• NMR Spectroscopy: ¹H and ¹³C NMR spectra provide unambiguous confirmation of the peri-substitution pattern. The protons adjacent to the amine and bromide groups display characteristic downfield shifts consistent with the electron-withdrawing effect of bromine and the ring-current anisotropy of the naphthalene system.
• HPLC or GC Purity: Chromatographic purity assessment (typically ≥97% for research-grade material) ensures that isomeric impurities such as 5-bromonaphthalen-1-amine or other regioisomers are absent at levels that would affect downstream chemistry.
• Mass Spectrometry: High-resolution mass spectrometry (HRMS) confirms the molecular ion at m/z 221/223 (reflecting the characteristic 1:1 isotope pattern of bromine) consistent with C₁₀H₈BrN.

Always request and review the Certificate of Analysis (CoA) and SDS from Aladdin Scientific prior to commencing experiments.

Frequently asked questions

What makes 8-Bromonaphthalen-1-amine useful as a synthetic building block?

8-Bromonaphthalen-1-amine contains two orthogonally reactive functional groups—a primary arylamine and an aryl bromide—positioned at the sterically proximal peri sites (1,8) of the naphthalene ring. This dual functionality enables sequential or selective transformations, such as palladium-catalyzed cross-coupling at the C–Br bond and acylation or cyclisation at the –NH2 group, providing efficient access to complex 1,8-disubstituted naphthalene architectures.

Which cross-coupling reactions are compatible with 8-Bromonaphthalen-1-amine?

The aryl bromide functionality supports a range of palladium-catalyzed cross-coupling protocols, including Suzuki–Miyaura (with arylboronic acids), Sonogashira (with terminal alkynes), Heck (with alkenes), and Buchwald–Hartwig amination reactions. Copper-mediated Ullmann-type couplings may also be feasible. Reaction conditions should be optimised for the specific coupling partner and catalyst system employed.

How should 8-Bromonaphthalen-1-amine be stored to maintain stability?

Store 8-Bromonaphthalen-1-amine in a tightly sealed container under cool, dry, and dark conditions, away from moisture, strong oxidisers, and acidic vapours. Refer to the product label and Certificate of Analysis for the manufacturer-recommended temperature range. For long-term storage, inert-atmosphere packaging (e.g., under argon or nitrogen) is advisable to prevent oxidative degradation of the amine group.

Is 8-Bromonaphthalen-1-amine the same compound as 8-bromo-1-naphthylamine?

Yes. 8-Bromonaphthalen-1-amine and 8-bromo-1-naphthylamine are two accepted IUPAC-based and common names for the same compound with CAS number 19819-98-8 and molecular formula C10H8BrN. Researchers may encounter either name in the literature or on supplier catalogues.

What analytical methods confirm the identity and purity of this reagent?

Identity is typically confirmed by 1H and 13C NMR spectroscopy (verifying the peri-substitution pattern) and high-resolution mass spectrometry (molecular ion at m/z 221/223, characteristic bromine isotope pattern). Purity is assessed by HPLC or GC analysis. Always request the lot-specific Certificate of Analysis from Aladdin Scientific before use.

References

1. Clayden, J.; Greeves, N.; Warren, S. Organic Chemistry, 2nd ed.; Oxford University Press: Oxford, 2012. General reference for arylamine and aryl halide reactivity.
2. Johansson Seechurn, C. C. C.; Kitching, M. O.; Colacot, T. J.; Snieckus, V. Palladium-Catalyzed Cross-Coupling: A Historical Contextual Perspective to the 2010 Nobel Prize. Angew. Chem. Int. Ed. 2012, 51, 5062–5085. doi:10.1002/anie.201107017
3. Aladdin Scientific Certificate of Analysis for 8-Bromonaphthalen-1-amine, SKU B589695. Retrieved from Aladdin Scientific product portal.

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