2,4-Dinitro Fluoro Benzene
A fluorine analogue of DNCB supplied by Chelora Chemicals — historically known as Sanger's reagent for its role in identifying the N-terminal amino acid of insulin, and still used today in biochemical analysis — exported from Indonesia with full batch documentation on every shipment.
What 2,4-Dinitro Fluoro Benzene is, and why buyers source it
A working overview of the compound's chemistry, its landmark history in protein sequencing, and the grades Chelora Chemicals keeps in regular supply.
2,4-Dinitro Fluoro Benzene (DNFB) is the fluorine analogue of 2,4-Dinitrochlorobenzene, carrying a fluorine in place of the chlorine on the same dinitro-activated ring. As with the activated-fluorine chemistry elsewhere in our range, the two nitro groups make the ring carbon bearing the fluorine exceptionally reactive toward nucleophilic aromatic substitution — here reinforced further by fluoride's favourable SNAr transition-state energetics once the ring is this strongly activated, making DNFB's fluorine, if anything, even more readily displaced than DNCB's chlorine.
With a melting point very close to ambient temperature, it is supplied as either a pale yellow crystalline solid or a low-melting liquid depending on storage conditions. It is practically insoluble in water but dissolves in common organic solvents, and is handled with particular care given its acute toxicity and mutagenicity/carcinogenicity hazard profile — full details are given below.
Where it fits in the synthesis chain
DNFB holds a specific place in the history of biochemistry as Sanger's reagent: Frederick Sanger used it in 1945 to react selectively with the free N-terminal amino group of a polypeptide, allowing that terminal amino acid to be identified after hydrolysis — a technique he applied to insulin as part of the work that determined its amino-acid sequence. Although Edman degradation and other methods have since superseded DNFB for routine protein sequencing, it remains in current use with HPLC to distinguish and quantify reduced and oxidised glutathione and cysteine in biological samples, and more broadly as a reactive dinitrophenylating reagent in biochemical and analytical research.
Grades we supply
Chelora Chemicals offers 2,4-Dinitro Fluoro Benzene in technical grade (≈97% assay) for standard industrial synthesis, and high-purity grade (99%+) for analytical and research applications sensitive to colour or isomeric carryover. Both grades are supplied with a batch-wise certificate of analysis.
How 2,4-Dinitro Fluoro Benzene is made
An overview of the production route for orientation purposes. Our manufacturing partners' own process parameters and in-process controls are proprietary and are not disclosed beyond what is needed to interpret the certificate of analysis.
2,4-Dinitro Fluoro Benzene is manufactured by the Halex (halogen-exchange) fluorination of 2,4-Dinitrochlorobenzene with potassium fluoride — the original preparation, reported by Gottlieb in 1936, reacted 1-chloro-2,4-dinitrobenzene with potassium fluoride in nitrobenzene as solvent, and the same general halogen-exchange logic underlies the modern industrial route.
After the halogen-exchange step, the crude product is separated from residual potassium chloride and solvent, washed, and crystallised or distilled to the required purity and colour before packing.
Why start from DNCB rather than fluorobenzene
As with the mono-nitro fluoronitrobenzenes elsewhere in our range, direct nitration of fluorobenzene is not the practical industrial route here; starting from the already-available 2,4-Dinitrochlorobenzene and converting its chlorine to fluorine via Halex is the standard way to reach this activated dinitrofluoroaromatic.
Industries and processes that use it
2,4-Dinitro Fluoro Benzene is consumed mainly as an analytical and biochemical research reagent, historically significant for protein sequencing and still in current use for specific analytical applications. The fields below cover the uses we see most often through our export desk.
Glutathione & Cysteine HPLC Analysis
Currently used with HPLC to distinguish and quantify reduced and oxidised glutathione and cysteine in biological samples, exploiting its reactive, readily displaced fluorine.
Dinitrophenylating Reagent for Biochemistry
A general-purpose reagent for selectively dinitrophenylating free amino groups and other nucleophilic sites in biochemical and analytical research.
Historical Protein Sequencing Reagent
Known as Sanger's reagent for its historical role identifying the N-terminal amino acid of polypeptides, including Frederick Sanger's 1945 work on insulin.
Fine-Chemical & Specialty Synthesis
Used more broadly as a highly activated dinitrofluoroaromatic building block in specialty synthesis calling for a readily displaced aryl fluoride.
How the molecule is typically carried forward
The fluorine, activated by two nitro groups at once, is an exceptionally reactive SNAr handle. Reaction classes below cover the main ways this material is used.
Reaction with Primary Amines (N-Terminal Labelling)
The fluorine is displaced by the free amino group of an amino acid or peptide N-terminus under mild aqueous/organic conditions, giving a stable dinitrophenyl (DNP) derivative — the basis of its historical use in protein sequencing.
Reaction with Thiols (Glutathione / Cysteine Analysis)
The fluorine is displaced by the thiol group of glutathione or cysteine to give a DNP-thioether derivative suitable for HPLC detection and quantification.
Reaction with Alkoxides & Other Nucleophiles
A broad range of other nucleophiles, including alkoxides and anilines, displace the fluorine under comparably mild SNAr conditions, owing to the strong doubly-activated reactivity.
Reduction of the Nitro Groups
Under controlled catalytic hydrogenation, the nitro groups can be reduced to amines; this is a less common route than direct fluorine displacement and requires particular care given the molecule's sensitivity.
2,4-Dinitro Fluoro Benzene against other nitroaromatic building blocks we supply
Buyers sourcing DNFB often want to compare it with its chlorine analogue, DNCB, for a different reactivity or cost profile. A quick reference to what else is on our regular supply list.
| Product | CAS Number | Category | Notes |
|---|---|---|---|
| 2,4-Dinitro Fluoro Benzene | 70-34-8 | Fluoro-dinitro aromatic | The product on this page — made by Halex fluorination of DNCB; the most reactive halide in this comparison. |
| 2,4-Dinitrochlorobenzene | 97-00-7 | Chloro-dinitro aromatic | The chlorine analogue and Halex starting material for this product — see its product page. |
| Para Fluoro Nitro Benzene | 350-46-9 | Mono-fluoro mono-nitro aromatic | A less heavily activated fluoronitroaromatic relative — see its product page. |
| Meta Dinitrobenzene | 99-65-0 | Di-nitro aromatic | A related dinitroaromatic without a halogen substituent — see its product page. |
Exact physical constants and purity specifications are confirmed per batch on the certificate of analysis — treat the notes above as a sourcing guide, not a specification sheet, for products other than 2,4-Dinitro Fluoro Benzene.
Safety classification at a glance
Based on GHS classification as commonly listed for this substance. This is a summary for orientation only — always work from the current safety data sheet supplied with your specific batch.
Toxic if swallowed, in contact with skin or if inhaled.
May cause genetic defects.
May cause cancer.
As the fluorine analogue of DNCB, this compound should be assumed to carry comparable skin-sensitising and contact-irritant potential; treat any skin contact as significant.
As a dinitroaromatic, avoid conditions involving excessive heat, friction or shock during storage and handling.
Impervious gloves (double-gloving recommended), full-body protection, splash-proof eye protection and respiratory protection are the baseline for routine handling.
Crystalline material can generate dust; local exhaust ventilation is strongly recommended during transfer and weighing.
Danger — GHS06 toxic pictogram applies; additional classification details are in the MSDS.
This compound is acutely toxic by all three exposure routes and is classified as a mutagen and carcinogen, and should be assumed, as the fluorine analogue of the well-documented skin sensitiser DNCB, to carry comparable dermal hazard. It must be handled with impervious gloves, full-body protective clothing, splash-proof eye protection and suitable respiratory protection at all times, with zero tolerance for skin contact, and with care around heat, friction and shock as for other dinitroaromatics. Full first-aid, storage, spill and PPE guidance is in the MSDS issued with every shipment, and should be read in full before this material is handled.
Keeping it on spec between delivery and use
General storage guidance for this grade. Site-specific storage rules, segregation requirements and re-test intervals should follow your own EHS procedures and the MSDS issued with your batch.
Store in a cool, dry, well-ventilated area, away from direct sunlight, heat sources, friction and mechanical shock, in tightly closed original packaging and segregated from strong reducing agents and incompatible materials. Its melting point sits close to ambient temperature, so a container may arrive as a solid, a liquid, or a mix of both; handle accordingly and avoid generating dust if solid. If a batch is held past its retest date, re-check assay, melting point and colour before use.
How it ships from Indonesia
Standard packing and export terms for this product. Confirm exact figures against your order — they vary slightly by destination and quantity.
What travels with every batch
Specification is agreed before the purchase order, not discovered on arrival. Every shipment of 2,4-Dinitro Fluoro Benzene leaves with a documented, checkable paper trail.
Certificate of Analysis
Batch-wise assay, melting point range and colour, issued against the agreed specification so your QC team can check it, not just file it.
Safety Data Sheet
GHS-format SDS in English covering hazard classification, handling, storage, first-aid and spill response for the exact grade shipped.
Technical Data Sheet
Reference physical and chemical properties, recommended storage and typical applications, for internal circulation to your process or R&D teams.
Certificate of Origin
Confirms Indonesian origin for customs clearance and any preferential-duty claim at your destination port.
Dangerous Goods Declaration
UN packing group, classification and shipper's declaration prepared ahead of loading so documentation never holds up customs.
Third-Party Inspection
Independent pre-shipment inspection and re-sampling can be arranged on request, at your cost, for buyers who require it as a matter of policy.
Frequently asked questions
What buyers most often ask our sales desk about this grade.
01What is 2,4-Dinitro Fluoro Benzene (DNFB) used for?+
02What is the CAS number of DNFB?+
03How is DNFB made?+
04What purity grades does Chelora Chemicals supply?+
05Is DNFB hazardous?+
06Why was DNFB historically important in biochemistry?+
07What packing options are available?+
08How long does delivery take?+
09Can I get a sample before placing a bulk order?+
10Do you supply other nitroaromatic building blocks?+
Need 2,4-Dinitro Fluoro Benzene on spec, on time?
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