Hexane-d₁₄: Deuterated Solvent for NMR & Research

Hexane-d₁₄ is a fully deuterated form of n-hexane in which all fourteen hydrogen atoms are replaced by deuterium, making it a valuable non-interfering solvent and isotopic tracer for NMR spectroscopy and mechanistic research.

Chemical Name

Hexane-d₁₄ (tetradecadeuterohexane)

Molecular Formula

C₆D₁₄

Molecular Weight

100.27 g/mol (vs 86.18 g/mol for protiated hexane)

Deuterium Content

14 deuterium atoms per molecule; isotopic purity typically ≥99 atom % D

Primary Application

Lock solvent and non-interfering matrix in ¹H and ¹³C NMR spectroscopy

Physical State

Colorless liquid at room temperature

SKU

H121283

What Is Hexane-d₁₄ and How Is It Made?

Hexane-d₁₄, also referred to as perdeuterated hexane or tetradecadeuterohexane, is the fully deuterated isotopologue of n-hexane (C₆H₁₄). Every one of the fourteen hydrogen atoms in the parent molecule is replaced by a deuterium (²H) atom, yielding the molecular formula C₆D₁₄ and a molecular weight of approximately 100.27 g/mol.

Deuterium incorporation is typically achieved through catalytic hydrogen–deuterium exchange reactions or by synthesis from deuterium oxide (D₂O)-derived precursors under carefully controlled conditions. High-grade research reagents such as those supplied by Aladdin Scientific are manufactured to achieve isotopic purities of ≥99 atom % D, minimizing residual protiated impurities that could otherwise produce unwanted background signals in sensitive spectroscopic measurements.

Physically, Hexane-d₁₄ closely resembles its protiated counterpart: it is a colorless, volatile, flammable liquid with a mild hydrocarbon odor. However, the substitution of deuterium for hydrogen subtly shifts certain physical constants—including boiling point and density—due to the isotope effect, and dramatically alters the NMR spectral signature of the solvent relative to analyte signals.

Key Applications in NMR Spectroscopy and Isotope Research

NMR Lock Solvent: The most widespread use of Hexane-d₁₄ is as an NMR lock solvent for samples that are soluble in non-polar media. Modern NMR spectrometers rely on the deuterium signal from the solvent to maintain field–frequency lock, ensuring spectral stability throughout acquisition. Because C₆D₁₄ lacks ¹H nuclei, it produces no interfering proton background in ¹H NMR spectra, allowing clean observation of analyte resonances. Its residual solvent peak (from trace CHD₂— or CHD— species) appears at approximately δ 0.88 ppm in ¹H NMR and δ 13.9 ppm in ¹³C NMR, regions that are often free of analyte signals for many compound classes.

Non-polar Reaction Monitoring: Hexane-d₁₄ is used as a reaction medium when researchers need to monitor non-polar or lipophilic reaction mixtures directly by NMR without removing the sample from the reaction vessel. This is particularly valuable in organometallic chemistry, polymer chemistry, and catalysis research where aqueous or polar solvents would perturb the system.

Isotope Labeling and Tracer Studies: In mechanistic and metabolic studies, perdeuterated hydrocarbons serve as internal standards or isotopic tracers. Hexane-d₁₄ can be employed in diffusion studies, membrane permeability assays, and environmental tracer experiments where the deuterium label provides a distinct mass spectrometric signature distinguishable from background hydrocarbon contamination.

Calibration and Reference Standards: High-purity Hexane-d₁₄ is used as a matrix-matched solvent reference in quantitative NMR (qNMR) and in the preparation of certified reference materials for analytical method validation.

Physicochemical Properties and Spectral Reference Data

A thorough understanding of the physical and spectroscopic properties of Hexane-d₁₄ allows researchers to design experiments correctly and interpret data accurately. Key properties are summarized below:

• Molecular formula: C₆D₁₄
• Molecular weight: ~100.27 g/mol
• Appearance: Colorless liquid
• Boiling point: Slightly elevated relative to protiated hexane (bp ~69 °C) due to the deuterium isotope effect; precise value should be confirmed from the certificate of analysis.
• Density: Higher than protiated hexane (~0.659 g/mL for n-hexane) due to the greater mass of deuterium; confirm exact value from supplier documentation.
• Residual ¹H NMR chemical shift: ~δ 0.88 ppm (CHD₂ and CHD residuals)
• ¹³C NMR chemical shift: ~δ 13.9 ppm (terminal CH₃) and ~δ 22.7 ppm (internal CH₂) for residual carbon signals
• Isotopic purity: ≥99 atom % D (typical for research-grade material)
• Miscibility: Miscible with most non-polar organic solvents; immiscible with water

Note: Precise physical constants may vary slightly by lot. Always consult the certificate of analysis (CoA) provided with each shipment for lot-specific data.

Safe Handling, Storage, and Regulatory Considerations

Flammability: Like protiated n-hexane, Hexane-d₁₄ is a highly flammable liquid and vapor. It must be kept away from open flames, sparks, and other ignition sources. Work should be performed in a well-ventilated fume hood, and appropriate fire-resistant storage cabinets should be used.

Health Hazards: Prolonged or repeated skin exposure to hexane isomers is associated with peripheral neuropathy; while studies on deuterated analogues are limited, the same precautions should be applied. Use chemical-resistant gloves (nitrile recommended), safety goggles, and a lab coat. Avoid inhalation of vapors.

Storage: Store in a tightly sealed container in a cool, dry, well-ventilated area away from heat sources and oxidizing agents. Because high isotopic purity is critical for NMR applications, minimize headspace exposure to atmospheric moisture (H₂O), which can introduce H/D back-exchange over time and degrade isotopic purity. Storage under inert gas (nitrogen or argon) is recommended after first opening.

Regulatory Status: Hexane-d₁₄ is a research chemical. Users should consult local regulations regarding flammable solvent storage limits, waste disposal requirements, and transport classification. Standard flammable-liquid IATA/IMDG shipping restrictions apply.

Disposal: Dispose of waste material in accordance with institutional, local, and national hazardous-waste regulations for flammable organic solvents. Do not pour down the drain.

Ordering Hexane-d₁₄ from Aladdin Scientific

Aladdin Scientific supplies Hexane-d₁₄ (SKU: H121283) for research and analytical applications. When placing an order, consider the following:

• Quantity: Select the pack size appropriate for your anticipated usage; minimize unnecessary opening of ampoules or bottles to preserve isotopic integrity.
• Certificate of Analysis: A lot-specific CoA confirming isotopic purity (atom % D), appearance, and other QC parameters is available upon request or via the Aladdin Scientific website.
• Lead Time and Availability: Deuterated solvents are specialty chemicals; confirm current stock availability and lead times with your Aladdin Scientific representative or through the online ordering portal.
• Shipping: This product is classified as a flammable liquid for shipping purposes. Hazardous-goods surcharges and packaging requirements apply. Aladdin Scientific ensures compliant packaging for domestic and international shipments.
• Custom Requirements: For large-volume needs, custom isotopic purity specifications, or bulk pricing, contact Aladdin Scientific customer service directly.

For the most current pricing, availability, and safety data sheet (SDS), visit the Aladdin Scientific product page for H121283 or contact your regional sales representative.

Frequently asked questions

What makes Hexane-d₁₄ suitable as an NMR solvent for non-polar compounds?

Hexane-d₁₄ provides a non-polar, aprotic matrix that dissolves lipophilic and non-polar analytes without altering their conformation or reactivity. Because all fourteen hydrogen atoms are replaced by deuterium, it generates no ¹H background signal and supplies the deuterium lock signal required for spectrometer field stabilization. Its residual solvent peaks appear at δ ~0.88 ppm (¹H) and δ ~13.9/22.7 ppm (¹³C), regions often clear of analyte resonances.

How should I store Hexane-d₁₄ to maintain its isotopic purity?

Store Hexane-d₁₄ in a tightly sealed container in a cool, dry, well-ventilated flammable-materials cabinet. After first opening, blanket the remaining solvent with dry inert gas (nitrogen or argon) to prevent back-exchange with atmospheric moisture (H₂O), which can gradually replace deuterium with protium and reduce isotopic purity. Avoid repeated opening and closing of the original container.

Can Hexane-d₁₄ be used in mass spectrometry experiments?

Yes. Hexane-d₁₄ can be used as an isotopically labeled internal standard or tracer in mass spectrometry, particularly in GC-MS or LC-MS workflows where a deuterium-labeled analog of the analyte matrix is needed for quantification or mechanistic studies. The 14-mass-unit shift relative to protiated hexane provides a clear, non-overlapping isotope cluster for detection and differentiation from unlabeled compounds.

What is the difference between Hexane-d₁₄ and partially deuterated hexane?

Hexane-d₁₄ is fully (perdeuterated) substituted, meaning all 14 hydrogen atoms are replaced by deuterium (C₆D₁₄, ≥99 atom % D). Partially deuterated hexane contains a mixture of isotopologues with varying numbers of deuterium atoms. For NMR lock applications and quantitative isotope tracer studies, the fully deuterated form is strongly preferred because residual ¹H signals from partial deuteration would introduce spectral noise and reduce the reliability of isotope ratios.

References

1. Fulmer, G. R. et al. NMR Chemical Shifts of Common Laboratory Solvents as Trace Impurities. Organometallics 2010, 29, 2176–2179. doi:10.1021/om100106e
2. Gottlieb, H. E.; Kotlyar, V.; Nudelman, A. NMR Chemical Shifts of Common Laboratory Solvents as Trace Impurities. J. Org. Chem. 1997, 62, 7512–7515. doi:10.1021/jo9703573
3. Aladdin Scientific. Product Page: Hexane-d₁₄, SKU H121283. Aladdin Scientific Co., Shanghai.

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