Para Nitrobenzoic Acid
Para Nitrobenzoic Acid is the documented precursor to procaine and to para-aminobenzoic acid (PABA), itself a folic-acid synthesis intermediate — a long-established pharmaceutical building block made by oxidation of 4-nitrotoluene, not nitration of benzoic acid.
What Para Nitrobenzoic Acid is, and why buyers source it
A working overview of the compound's chemistry, its place in the aniline-derivative family, and the grades Chelora Chemicals keeps in regular supply.
Para Nitrobenzoic Acid (PNBA) is a simple, well-characterised aromatic compound: a nitro group and a carboxylic acid group positioned opposite each other on the benzene ring. We want to correct a plausible-sounding assumption directly: the documented industrial route to this compound is oxidation of 4-nitrotoluene, not nitration of plain benzoic acid — the two routes would give the same product in principle, but the nitrotoluene oxidation route is the one actually used at scale.
Its real, documented pharmaceutical-chain significance is as a precursor, via its acid chloride, to procaine (a classic local anesthetic), and separately as a route to para-aminobenzoic acid (PABA) by reduction of the nitro group — PABA itself being a documented intermediate in folic acid (vitamin B9) synthesis. Dye-intermediate use is commonly claimed by suppliers in the trade, but we were not able to independently confirm a specific, documented dye-chemistry application in primary sources, so we note that claim honestly as supplier-reported rather than independently verified.
Where it fits in the synthesis chain
We supply Para Nitrobenzoic Acid itself. We do not manufacture or supply procaine, PABA, folic acid, or any other finished pharmaceutical product made from it.
Grades we supply
98% and 99% grades are both seen across the trade; pharmaceutical-intermediate buyers typically specify the higher grade.
How Para Nitrobenzoic Acid 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.
Para Nitrobenzoic Acid is made industrially by oxidation of 4-nitrotoluene, using either oxygen under catalytic conditions or a dichromate oxidant, converting the methyl group directly to the carboxylic acid while leaving the nitro group untouched.
This oxidation route is the documented industrial process — we want to be clear that nitration of benzoic acid itself, while chemically plausible as an alternative on paper, is not the route actually used at scale for this compound, and we correct that assumption here rather than let it stand unchallenged.
The crude product is purified by crystallisation, taking advantage of its high melting point and low water solubility to separate it cleanly from unreacted starting material and over-oxidised by-products before drying to the finished powder.
A route correction worth making explicit
It would be reasonable to assume this compound is made by nitrating benzoic acid directly, since that mirrors how several other nitro-substituted building blocks in the broader trade are made. The documented industrial process for this specific compound is different: oxidation of 4-nitrotoluene's methyl group to the carboxylic acid. We state the correct, documented route rather than the plausible-sounding alternative.
Industries and processes that use it
Para Nitrobenzoic Acid is consumed almost entirely as a synthesis intermediate. The four fields below account for most of the demand we see through our export desk.
Procaine & Local Anesthetic Synthesis
Via its acid chloride, this compound is a documented precursor in the synthesis of procaine, a classic local anesthetic.
PABA & Folic Acid Synthesis Chain
Reduction of the nitro group gives para-aminobenzoic acid (PABA), itself a documented intermediate in folic acid (vitamin B9) synthesis.
General Fine-Chemical Intermediate
Used more broadly as a building block in fine-chemical synthesis wherever this specific nitro/carboxylic-acid substitution pattern is required; dye-intermediate use is commonly claimed by suppliers but was not independently confirmed in the sources we checked.
How the molecule is typically carried forward
Para Nitrobenzoic Acid offers two independent reactive handles: the carboxylic acid, activated to its acid chloride for further synthesis, and the nitro group, reduced when the target is the corresponding amine.
Acid chloride formation
Reaction with thionyl chloride or a similar reagent converts the carboxylic acid to the corresponding acid chloride, the activated form used in procaine synthesis and other acylation chemistry.
Reduction of the nitro group
Catalytic or chemical reduction converts the nitro group to an amine, giving para-aminobenzoic acid (PABA), the documented folic-acid-chain intermediate.
Amide formation
Reaction with ammonia or an amine, via the acid chloride, gives the corresponding amide — the same general chemistry used to make Para Nitrobenzamide, the related product elsewhere in this part of our range.
Para Nitrobenzoic Acid against its near relatives
Para Nitrobenzoic Acid and Para Nitrobenzamide are the two nitrobenzene-derivative intermediates in this part of our range, related as acid and amide forms of the same core structure.
| Product | CAS Number | Typically Used In | Notes |
|---|---|---|---|
| Para Nitrobenzoic Acid | 62-23-7 | Procaine and PABA/folic acid synthesis chain | The product on this page. |
| Para Nitrobenzamide | 619-80-7 | Pharmaceutical and fine-chemical intermediate | Also supplied — 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 rather than a specification sheet.
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.
Causes skin irritation.
Causes serious eye irritation.
May cause respiratory irritation.
Warning
No harmonised EU CLP Annex VI entry was located for this substance. The classification above reflects general irritant self-classification consistent with its acidic, mildly irritant character. IARC has not evaluated this specific compound — we checked specifically, since several related nitro/amino-nitrobenzene isomers do appear in IARC's broader review scope, but this compound itself has not been separately evaluated.
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 area away from strong bases and oxidisers, consistent with its character as a carboxylic acid. Keep containers tightly sealed.
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 Para Nitrobenzoic Acid leaves with a documented, checkable paper trail.
Certificate of Analysis
Batch-wise assay (by GC), isomer purity, melting point range and moisture, 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 Para Nitrobenzoic Acid used for?+
02What is the CAS number of Para Nitrobenzoic Acid?+
03What purity grades does Chelora Chemicals supply?+
04Is Para Nitrobenzoic Acid hazardous?+
05Is this made by nitrating benzoic acid?+
06Do you supply procaine, PABA or folic acid directly?+
07Is the dye-intermediate use you sometimes see mentioned for this compound confirmed?+
08What packing options are available?+
09How long does delivery take?+
10Can I get a sample before placing a bulk order?+
11How is Para Nitrobenzoic Acid manufactured?+
12What is the shelf life, and how should it be stored?+
Need Para Nitrobenzoic Acid on spec, on time?
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