1,4-Dibromobenzene-d4 CAS No.: 4165-56-4

1,4-Dibromobenzene-d4 | CAS No.: 4165-56-4

Chemical Name: 1,4-Dibromobenzene-d4
Synonyms: p-Dibromobenzene-d4, Para-dibromobenzene-d4, Benzene, 1,4-dibromo-d4
Molecular Formula: C₆D₄Br₂
Molecular Weight: 239.93 g/mol
Isotopic Enrichment: ≥ 98 atom % D
Chemical Structure: Fully deuterated aromatic ring with bromine atoms at para positions

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Product Description

1,4-Dibromobenzene-d4 is a high-purity deuterated isotopologue of 1,4-dibromobenzene, in which four aromatic hydrogen atoms are replaced with deuterium. This deuterium substitution provides a distinctive isotopic signature while retaining the identical chemical and physical properties of its non-deuterated analog.

As a stable isotopic compound, 1,4-Dibromobenzene-d4 serves as a reference material, NMR solvent standard, and internal standard in analytical and spectroscopic applications. Its symmetrical para-substitution pattern makes it an excellent benchmark for spectroscopic calibration, molecular symmetry studies, and isotopic tracer investigations.

In the chemical industry, it also finds utility as a starting material for the synthesis of labeled aromatic intermediates, particularly in halogen-exchange and cross-coupling reactions such as Suzuki and Stille couplings.

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Applications of 1,4-Dibromobenzene-d4 CAS No. 4165-56-4

1. Internal Standard in Analytical Chemistry

1,4-Dibromobenzene-d4 is widely employed as an internal standard in GC-MS and LC-MS analyses for halogenated aromatic compounds. The deuterium atoms shift the molecular mass by +4 units, enabling precise distinction between analyte and reference peaks. It is particularly valuable in:

• Quantitative analysis of brominated compounds

• Residual solvent and impurity profiling in pharmaceuticals

• Environmental trace analysis of brominated pollutants and flame retardants

The isotopic substitution ensures equivalent chromatographic behavior while allowing accurate mass-based discrimination, which is critical for isotope dilution mass spectrometry (IDMS).

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2. NMR Spectroscopy and Calibration

Because of its high symmetry and strong aromatic signals, 1,4-Dibromobenzene-d4 is frequently used as an NMR calibration standard. Its deuterated ring minimizes background proton interference in ^1H NMR spectra, providing a clean baseline for instrument tuning and solvent signal suppression tests.

In solid-state NMR, it is used to examine quadrupolar coupling and spin-relaxation phenomena. The molecule’s simple yet rigid structure makes it a favored choice for understanding molecular motions and isotropic averaging effects in crystalline solids.

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3. Synthetic Applications

In organic synthesis, 1,4-Dibromobenzene-d4 serves as a precursor for labeled intermediates. It participates in various metal-catalyzed cross-coupling reactions, including:

• Suzuki–Miyaura coupling for labeled biphenyl synthesis

• Heck and Stille couplings to produce deuterated styrene or vinyl derivatives

• Grignard reactions for producing isotopically enriched phenylmagnesium reagents

These reactions are important for the synthesis of deuterated pharmaceuticals and labeled reference compounds used in drug metabolism and pharmacokinetic (DMPK) studies.

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4. Environmental and Mechanistic Studies

Brominated aromatic compounds are key analytes in environmental monitoring, particularly for assessing halogenated flame retardant contamination. 1,4-Dibromobenzene-d4 acts as an isotopic tracer in studies investigating bromine transfer, photodegradation, and combustion mechanisms. Its stable isotope label allows researchers to track molecular transformations with high specificity and sensitivity.

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Synthesis and Quality Assurance

1,4-Dibromobenzene-d4 is synthesized through selective deuterium exchange reactions on benzene-d6, followed by controlled bromination under para-directing conditions. This ensures high positional selectivity and uniform isotopic distribution across all four deuterium sites.

Each production batch undergoes rigorous testing to ensure chemical and isotopic integrity:

• ¹H and ²H NMR Spectroscopy – confirms full deuteration and structural identity

• Mass Spectrometry (GC-MS / LC-MS) – verifies molecular weight and isotopic distribution

• HPLC Purity Analysis – ensures chemical purity ≥ 98 %

Every lot is accompanied by a Certificate of Analysis (CoA) listing deuterium enrichment, purity, and analytical verification data.

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Storage and Handling of 1,4-Dibromobenzene-d4 CAS No. 4165-56-4

Store 1,4-Dibromobenzene-d4 in airtight, light-protected containers at ambient or refrigerated temperature (2–8 °C). Avoid prolonged exposure to light, heat, and air to prevent degradation or halogen exchange.

Use standard laboratory protective measures—gloves, goggles, and lab coat—when handling. Dispose of materials according to local environmental and chemical safety regulations for brominated compounds.

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Key Advantages

• High isotopic purity (≥ 98 atom % D)

• Excellent stability and reproducibility for analytical use

• Ideal for NMR calibration and isotopic labeling studies

• Serves as an effective internal standard in GC-MS

• Available in research and bulk quantities with complete CoA support

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Ordering Information

For inquiries, bulk orders, or custom isotopic labeling projects, contact ResolveMass Laboratories Inc. at info@resolvemass.ca.

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Summary

1,4-Dibromobenzene-d4 (CAS 4165-56-4) is a fully deuterated para-dibromo aromatic compound used as an analytical standard, NMR reference, and synthetic precursor for isotopically labeled materials. Combining high isotopic enrichment with excellent chemical stability, it supports precision analysis in environmental, pharmaceutical, and materials chemistry research.