7-Bromo-3,4-dihydroquinazolin-4-one: Key Facts & FAQs

7-bromo-3,4-dihydroquinazolin-4-one is a brominated bicyclic heterocyclic compound widely used as a versatile synthetic building block in medicinal chemistry for the preparation of biologically active quinazolinone derivatives.

Chemical Name

7-bromo-3,4-dihydroquinazolin-4-one

SKU / Catalog Number

B175428

Molecular Formula

C8H5BrN2O

Molecular Weight

213.04 g/mol

Core Scaffold

Quinazolin-4(3H)-one (bicyclic benzene-fused pyrimidone)

Key Functional Handle

C-7 aryl bromide — suitable for cross-coupling reactions (Suzuki, Buchwald-Hartwig, etc.)

Supplier

Aladdin Scientific

What Is 7-Bromo-3,4-dihydroquinazolin-4-one?

7-Bromo-3,4-dihydroquinazolin-4-one (also written as 7-bromoquinazolin-4(3H)-one) belongs to the quinazolinone family of bicyclic heterocycles, consisting of a benzene ring fused to a pyrimidone ring. The bromine substituent at the 7-position of the aromatic ring provides a reactive handle that can be exploited in a wide range of palladium-catalyzed cross-coupling reactions, nucleophilic aromatic substitution, and metal-halogen exchange reactions. The lactam nitrogen (N-3) and the carbonyl at C-4 are characteristic of the 4(3H)-one tautomeric form, which predominates in the solid state.

The compound is of significant interest in drug discovery because the quinazolin-4-one core appears in numerous pharmacologically active natural products and synthetic drug candidates, including compounds with reported kinase-inhibitory, antimicrobial, and anticancer properties.

Chemical and Physical Properties

The molecular formula of 7-bromo-3,4-dihydroquinazolin-4-one is C₈H₅BrN₂O, giving a molecular weight of approximately 213.04 g/mol. The presence of a heavy bromine atom (atomic weight ~79.9) accounts for a substantial fraction of the molecular weight. The compound is expected to appear as a solid at room temperature, consistent with other halogenated quinazolinone analogues.

Key physicochemical considerations for researchers include:

• Solubility: Quinazolinone derivatives are generally sparingly soluble in water but dissolve in polar aprotic solvents such as DMSO, DMF, and acetonitrile. Always verify solubility empirically for your specific application.
• Stability: The aryl C–Br bond is stable under normal ambient conditions; however, prolonged exposure to strong bases or nucleophiles may affect the heterocyclic ring system. Store under inert atmosphere if long-term stability is required.
• pKa: The N-3 H of the lactam is weakly acidic. Deprotonation under strongly basic conditions can facilitate N-alkylation chemistry.

Note: Specific melting point, logP, and spectroscopic data (NMR, IR) are not included in the supplied source material. Consult the product certificate of analysis (CoA) available through Aladdin Scientific for confirmed lot-specific data.

Synthetic Applications and Reactivity

The 7-bromo substituent makes this compound an excellent partner in transition-metal-catalyzed reactions. Researchers commonly employ it in the following transformations:

• Suzuki–Miyaura coupling: Reaction with aryl- or heteroarylboronic acids in the presence of a palladium catalyst (e.g., Pd(PPh₃)₄ or Pd(dppf)Cl₂) and base introduces diverse (hetero)aryl groups at the 7-position, enabling rapid library synthesis around the quinazolinone core.
• Buchwald–Hartwig amination: The aryl bromide can be converted to arylamines using palladium catalysis with appropriate phosphine ligands and amine coupling partners.
• Sonogashira coupling: Terminal alkynes can be introduced at C-7 under Pd/Cu co-catalysis to give 7-alkynylquinazolinone products useful as probes or further functionalization handles.
• N-3 functionalization: The lactam NH can be alkylated, acylated, or otherwise functionalized independently of the aryl bromide, allowing orthogonal two-point diversification of the scaffold.

These attributes collectively make 7-bromo-3,4-dihydroquinazolin-4-one a high-value building block for fragment-based drug discovery and parallel medicinal chemistry campaigns.

Storage, Handling, and Safety

Although specific GHS hazard classifications for this exact compound are not detailed in the supplied product information, the following general guidance applies to halogenated heterocyclic research chemicals:

• Storage: Store in a tightly sealed container in a cool, dry, well-ventilated area, away from light and moisture. Refrigerated storage (2–8 °C) is commonly recommended for long-term stability of similar compounds. Check the Aladdin Scientific product page and CoA for lot-specific recommendations.
• Personal protective equipment (PPE): Wear appropriate laboratory gloves, safety glasses, and a lab coat when handling. Work in a fume hood when weighing or dissolving the compound to avoid inhalation of dust or aerosols.
• Disposal: Dispose of waste material in accordance with local, regional, and national chemical waste regulations. Do not dispose of down the drain.
• SDS: Always consult the Safety Data Sheet (SDS) provided by Aladdin Scientific before use. The SDS contains authoritative hazard, first-aid, and emergency-response information specific to this product lot.

Ordering and Specifications

7-Bromo-3,4-dihydroquinazolin-4-one is available from Aladdin Scientific under catalog number B175428. When placing an order, researchers and procurement teams should confirm the following with the product listing or by contacting Aladdin Scientific customer support:

• Purity grade: Confirm the purity specification (e.g., ≥95%, ≥97%, or higher) suitable for your synthetic or biological application. A certificate of analysis (CoA) with HPLC or NMR data should accompany each lot.
• Pack sizes: Available pack sizes and pricing are listed on the Aladdin Scientific website. Contact sales for bulk or custom quantity inquiries.
• Lead time: Standard and expedited shipping options may be available depending on stock status and your location.
• Returns and quality issues: Refer to Aladdin Scientific's returns and refund policy. If the product does not meet stated specifications, contact customer service with your order number and CoA discrepancy details.

Frequently asked questions

What is the molecular formula and molecular weight of 7-bromo-3,4-dihydroquinazolin-4-one?

The molecular formula is C8H5BrN2O and the molecular weight is approximately 213.04 g/mol. The bromine atom at the 7-position contributes significantly to the molecular weight of this bicyclic quinazolinone scaffold.

What solvents can be used to dissolve 7-bromo-3,4-dihydroquinazolin-4-one?

Like most quinazolinone derivatives, this compound is expected to be sparingly soluble in water but soluble in polar aprotic solvents such as DMSO, DMF, and acetonitrile. Researchers should verify solubility empirically for their specific concentration and application requirements, as solubility can vary with lot and purity.

What cross-coupling reactions can be performed using 7-bromo-3,4-dihydroquinazolin-4-one?

The aryl bromide at C-7 is suitable for palladium-catalyzed Suzuki–Miyaura coupling with boronic acids, Buchwald–Hartwig amination with amines, and Sonogashira coupling with terminal alkynes, among other metal-catalyzed transformations. These reactions allow rapid diversification of the quinazolinone core for medicinal chemistry applications.

How should 7-bromo-3,4-dihydroquinazolin-4-one be stored to ensure stability?

The compound should be stored in a tightly sealed container in a cool, dry, and well-ventilated area away from light and moisture. For long-term storage, refrigerated conditions (2–8 °C) under an inert atmosphere are generally recommended for halogenated heterocyclic compounds of this type. Consult the Aladdin Scientific product CoA for lot-specific storage instructions.

What is the Aladdin Scientific catalog number for 7-bromo-3,4-dihydroquinazolin-4-one, and how can I order it?

The catalog number is B175428. You can place an order directly through the Aladdin Scientific website or by contacting the sales team. Be sure to confirm the available pack sizes, purity grade, and current stock status before ordering. For bulk quantities, contact Aladdin Scientific customer support for a customized quotation.

Is 7-bromo-3,4-dihydroquinazolin-4-one suitable for biological screening assays?

The quinazolin-4-one scaffold is well-represented in biologically active compounds, including kinase inhibitors and antimicrobial agents, making this compound a relevant candidate for biological screening. However, researchers should confirm the purity grade and perform appropriate solubility and stability assessments in biological media before use. No specific biological activity data for this exact compound is provided in the source material.

References

1. Mhaske, S. B.; Argade, N. P. The chemistry of recently isolated naturally occurring quinazolinone alkaloids. Tetrahedron 2006, 62 (42), 9787–9826. doi:10.1016/j.tet.2006.07.098
2. Aladdin Scientific. Product page: 7-Bromo-3,4-dihydroquinazolin-4-one, Catalog No. B175428. Aladdin Scientific, accessed 2024.
3. Miyaura, N.; Suzuki, A. Palladium-catalyzed cross-coupling reactions of organoboron compounds. Chem. Rev. 1995, 95 (7), 2457–2483. doi:10.1021/cr00039a007

Products are supplied for research and development use only. Not for use in humans, animals, diagnosis, or therapy.