Dimethyl Sulfate
The industrial methylating agent supplied by Chelora Chemicals — known in the trade as DMS, used under strictly controlled conditions to introduce methyl groups in dye, agrochemical and fine-chemical synthesis — exported from Indonesia in drums and ISO tanks with full batch documentation and dedicated handling protocols on every shipment.
What Dimethyl Sulfate is, and why buyers source it
A working overview of the compound's chemistry, its role as a powerful industrial methylating agent, and the grade Chelora Chemicals keeps in regular supply, together with the strict handling discipline this chemical requires.
Dimethyl Sulfate is the dimethyl ester of sulfuric acid, carrying two methyl groups attached through oxygen to a central sulfate unit. Both methyl groups are highly electrophilic and readily transferred to nucleophiles such as amines, phenols and carboxylate ions, which is exactly the reactivity that makes it one of the most efficient methylating agents available industrially — and, for the same chemical reason, one of the most hazardous.
At room temperature it is a colourless to faintly yellow, oily liquid with a faint, onion-like odour that becomes noticeable only well above the threshold at which serious exposure has already occurred, making odour an unreliable warning sign. It reacts slowly with atmospheric moisture to release methanol and sulfuric acid, and must be stored and handled under strictly controlled, moisture-free, well-ventilated conditions with dedicated engineering controls.
Where it fits in the synthesis chain
Dimethyl Sulfate's primary industrial use is as a methylating agent in the synthesis of dyes, pharmaceutical intermediates, agrochemicals and fine chemicals, where it efficiently introduces a methyl group onto a nitrogen, oxygen or sulfur nucleophile under controlled reaction conditions. It is used only by facilities with the specialised containment, scrubbing and emergency-response infrastructure this reagent requires, strictly under closed-system handling.
Grade we supply
Chelora Chemicals offers Dimethyl Sulfate in technical/industrial grade (99%+ assay) supplied exclusively to buyers with verified closed-system handling capability and full regulatory authorisation, accompanied by a batch-wise certificate of analysis and complete safety documentation.
How Dimethyl Sulfate 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.
Dimethyl Sulfate is manufactured by reacting methanol with sulfur trioxide (or oleum/chlorosulfonic acid, depending on the specific process route) under carefully controlled conditions: 2 CH₃OH + SO₃ → (CH₃)₂SO₄ + ... (process-specific byproducts). The reaction is run in specialised, fully enclosed equipment with integrated scrubbing systems given the product's hazard profile, and the crude product is purified by vacuum distillation.
Why this remains a tightly controlled, specialist manufacturing process
Because dimethyl sulfate is both the product and, if mishandled, an acute hazard in its own right, its manufacture is run exclusively in dedicated, fully enclosed plant with continuous containment and scrubbing, a very different operating discipline from most of the commodity chemicals in this catalogue.
Industries and processes that use it
Dimethyl Sulfate is consumed in specialist fine-chemical, dye and agrochemical methylation reactions, always under closed-system, tightly controlled conditions. The fields below account for the demand we see through our export desk, restricted to verified industrial buyers.
Dye & Pigment Intermediate Methylation
Used to introduce methyl groups onto amine and phenolic intermediates in dye and pigment synthesis, under closed-system reactor conditions.
Pharmaceutical Intermediate Methylation
Used in selected pharmaceutical fine-chemical synthesis routes requiring an efficient O- or N-methylation step, under full regulatory and safety oversight.
Agrochemical Intermediate Methylation
Used to methylate selected agrochemical intermediates in closed-system industrial synthesis.
Specialty Methylcellulose & Polymer Chemistry
Used in limited specialty polymer-methylation applications under the same strict closed-system handling discipline.
How the molecule is typically carried forward
The electrophilic methyl-sulfate linkage governs almost all of this molecule's reaction chemistry. Reaction classes below account for most of the ways Dimethyl Sulfate is used as a methylating reagent.
Nucleophilic Methylation (Primary Reaction)
A nucleophile (amine nitrogen, phenolic oxygen, or similar) attacks a methyl group on the sulfate centre, transferring the methyl group and releasing methyl sulfate anion, the core reaction behind all of DMS's industrial uses.
Hydrolysis (Degradation Pathway)
Reacts slowly with atmospheric or adventitious moisture to release methanol and sulfuric acid, a pathway that must be prevented during storage and handling.
Double Methylation (Process Chemistry)
Can transfer both methyl groups sequentially in some reaction schemes, a consideration in reaction stoichiometry and by-product management.
Sulfating Esterification (Upstream)
Methanol reacts with sulfur trioxide under closed-system conditions to form dimethyl sulfate itself, the dominant industrial route in the whole chain.
Dimethyl Sulfate against other amines we supply
Buyers sourcing Dimethyl Sulfate for verified, closed-system methylation applications often need the related ethylating agent. A quick reference to what else is on our regular supply list, subject to the same strict handling verification.
| Product | CAS Number | Category | Notes |
|---|---|---|---|
| Dimethyl Sulfate | 77-78-1 | Industrial methylating agent | The product on this page — supplied exclusively to verified closed-system industrial users. |
| Diethyl Sulfate | 64-67-5 | Industrial ethylating agent | The related ethylating agent used in similar fine-chemical synthesis — see its product page. |
| Methanol | 67-56-1 | Simplest aliphatic alcohol | The feedstock from which dimethyl sulfate is made — see its product page. |
| Caustic Soda (Sodium Hydroxide) | 1310-73-2 | Industrial alkali | Used for controlled neutralisation/deactivation of DMS process streams — 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 Dimethyl Sulfate.
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.
Toxic in contact with skin.
Fatal if inhaled.
May cause cancer.
Full-face supplied-air respiratory protection, chemical-resistant totally encapsulating suits and closed-system transfer equipment are mandatory — no open handling is permitted.
Fatal if inhaled, with effects that can be delayed; any suspected exposure is a medical emergency requiring immediate professional care.
Classified as a probable human carcinogen; exposure must be eliminated through engineering controls, not managed through PPE alone.
Danger — GHS06 acute toxicity and GHS08 carcinogen/health-hazard pictograms apply at the highest severity level.
This compound is toxic if swallowed or in contact with skin, is fatal if inhaled, and may cause cancer, with toxic effects that can be delayed well beyond the time of exposure. It is supplied only to buyers with verified closed-system handling infrastructure, full-face supplied-air respiratory protection, totally encapsulating chemical-resistant suits and dedicated emergency-response capability; open handling of this material is never acceptable. Any suspected exposure is a medical emergency requiring immediate professional care. The complete MSDS issued with every shipment must be read in full, and Chelora Chemicals requires documented proof of appropriate handling capability before supplying this product.
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 only in a dedicated, scrubbed, moisture-free facility designed specifically for high-hazard reactive chemicals, in sealed, corrosion-resistant original packaging, away from moisture, strong bases and amine-containing materials, with continuous vapour monitoring and emergency containment in place. This material must never be stored, handled or transferred outside a facility with documented closed-system capability. If a batch is held past its retest date, professional re-assessment is required before any further 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 Dimethyl Sulfate leaves with a documented, checkable paper trail.
Certificate of Analysis
Batch-wise assay (by titration/GC), colour and relevant physical constants, 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 of Dimethyl Sulfate 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 Dimethyl Sulfate used for?+
02What is the CAS number of Dimethyl Sulfate?+
03How is Dimethyl Sulfate made?+
04What verification does Chelora Chemicals require before supplying this material?+
05Why is Dimethyl Sulfate considered especially hazardous even among industrial chemicals?+
06Is Dimethyl Sulfate hazardous?+
07What packing options are available?+
08How long does delivery take?+
09Can I get a sample before placing a bulk order?+
10Do you supply Diethyl Sulfate as well?+
Need Dimethyl Sulfate on spec, on time?
Send us your required purity, quantity, packing preference and destination port. Our desk quotes most enquiries within one working day.