tert-Butylamine CAS 75-64-9

What is tert-Butylamine?

tert-Butylamine is the fully branched primary amine of the butyl series — an amino group on a quaternary carbon bearing three methyl groups, (CH₃)₃CNH₂. Like sec-butylamine it is a primary amine despite the name: the "tert" describes the carbon, not the nitrogen, which still carries two hydrogens.

That bulky tert-butyl group is the whole commercial story. It slows the nitrogen down sterically, which is sometimes a nuisance in synthesis, and it makes the resulting derivatives markedly more stable to hydrolysis and oxidation, which is almost always an advantage in the finished product. A tert-butyl substituent on a sulfenamide, a triazine or a drug molecule is usually there to buy stability.

It is a clear, colourless, highly volatile liquid boiling at about 45 °C, with a strong ammoniacal odour. The flash point is well below ambient and the boiling point is close enough to room temperature that warm drums build real pressure — so while it handles as a liquid, it demands more respect in storage than the heavier butylamines.

Commercially, tert-butylamine is dominated by one product: the benzothiazole sulfenamide accelerator used across the tyre industry, where the tert-butyl group delivers the delayed action and scorch safety that modern compounding depends on. Beyond that it supplies the tert-butylamino arm on major triazine herbicides and the tert-butylamino group in bronchodilator pharmaceuticals.

Why tert-butylamine specifically

• Steric bulk buys stability. The tert-butyl group shields adjacent bonds from hydrolysis and oxidation. In a sulfenamide accelerator that translates directly into scorch safety and shelf life.
• Delayed-action accelerator chemistry. The bulky amine is what makes a benzothiazole sulfenamide cure late and fast rather than early and slowly — the behaviour modern tyre compounding is built around.
• Distinctive biological profile. The tert-butylamino fragment appears deliberately in triazine herbicides and in beta-agonist pharmaceuticals, where it is part of the molecule's identity.
• Made from isobutylene, not butanol. Direct amination of isobutylene over a zeolite catalyst gives a different impurity profile from the alcohol-amination routes used for the other isomers.

How TBA is Manufactured

tert-Butylamine is made differently from the other butylamines. The tertiary carbon cannot be built by reductive amination of a carbonyl, so the industrial route adds ammonia directly across isobutylene.

• Direct amination of isobutylene. Isobutylene and ammonia are reacted over an acidic zeolite catalyst at elevated temperature and pressure. The ammonia adds across the double bond according to Markovnikov's rule, placing the nitrogen on the more substituted carbon and giving tert-butylamine directly.
• Equilibrium and recycle. The reaction is equilibrium-limited, so conversion per pass is modest and unreacted isobutylene and ammonia are separated and recycled. This is the main reason the product is made by a relatively small number of producers.
• Separation. The reactor effluent is separated from ammonia and light ends by distillation. Because tert-butylamine boils well clear of the other butylamine isomers, isomer carry-over is a smaller concern here than for the sec and iso products.
• Drying and finishing. The product is dried to specification and filled into pressure-capable drums, IBCs or tanks, with nitrogen blanketing where colour and water specification matter.

Typical Commercial Specification

Figures below are representative of standard commercial grade. Tighter rubber-chemical and pharmaceutical grades are available — send us the specification you work to and we will quote against it.

Physical & Chemical Properties

Reactivity in practice

The nitrogen is strongly basic but sterically crowded, which shapes everything it does. Four reaction types cover nearly all of its use:

• Sulfenamide formation. Reaction with a benzothiazole disulphide or sulfenyl chloride gives the delayed-action sulfenamide accelerators that dominate tyre compounding. The bulky amine is what delays the cure.
• Substitution on chlorotriazines. Displaces chloride from cyanuric chloride derivatives to install the tert-butylamino arm found on several selective triazine herbicides.
• Epoxide opening. Opens epoxide rings to tert-butylamino alcohols — the structural motif in beta-agonist bronchodilator pharmaceuticals.
• Hindered base chemistry. Because the nitrogen is crowded it acts as a base more readily than as a nucleophile in some systems, which is occasionally exploited to control selectivity.

tert-Butylamine vs the Other Butylamine Isomers

All four butylamine isomers share the formula C₄H₁₁N and a molecular weight of 73.14, and differ only in where the amino group sits on the four-carbon skeleton. That single difference moves the boiling point by more than 30 °C across the set, changes how crowded the nitrogen is, and decides which registered products the molecule can go into. They are separate substances with separate CAS numbers, not grades of one another.

Stated plainly: the more branched the carbon bearing the nitrogen, the lower the boiling point and the more crowded the amine. n-Butylamine is linear and reacts freely; isobutylamine is branched one carbon away and behaves similarly with slightly more bulk; sec-butylamine carries a chiral centre, which matters in pharmaceutical work; tert-butylamine is fully branched at the nitrogen-bearing carbon, which slows some reactions and makes the resulting derivatives notably more hydrolytically stable. Chelora supplies all four.

Industries We Supply TBA To

The same molecule leaves our warehouse for very different factories. What changes between them is not the CAS number but the grade, the packing and the documentation each sector expects.

Where TBA is Used

tert-Butylamine is dominated by rubber chemistry but valuable well beyond it. These are the end uses our customers buy it for, roughly in order of volume.

In tyre and rubber chemicals

This is the dominant outlet. tert-Butylamine is combined with benzothiazole chemistry to produce the sulfenamide accelerator that modern tyre compounding is built around. What makes it work is the bulk of the tert-butyl group: it delays the onset of cure, giving the processing safety — scorch resistance — that lets a compound be mixed, extruded and shaped before it starts to crosslink, then cures quickly once it reaches temperature. Water content on the incoming amine is the specification that matters, since the sulfur intermediates hydrolyse readily.

In triazine herbicide manufacture

Cyanuric chloride is substituted stepwise, and tert-butylamine supplies the tert-butylamino arm on several selective herbicides. The bulky group changes both the soil persistence and the weed spectrum relative to the ethyl and isopropyl analogues, which is why it is chosen deliberately rather than for cost. Plants running registered actives keep isomer and secondary amine figures under control for the usual reasons.

In pharmaceutical synthesis

Opening an epoxide with tert-butylamine gives a tert-butylamino alcohol — the structural core of a family of beta-adrenergic agonists used as bronchodilators. The bulky amine is part of what gives those molecules their receptor selectivity. API producers run the tightest specifications in the market, with residual tert-butanol and hydrocarbons from the isobutylene route, secondary amine carry-over and metals all needing to clear ICH limits.

As a hindered base

In fine chemical synthesis the steric crowding around the nitrogen is sometimes the point: tert-butylamine can deprotonate or neutralise without competing as a nucleophile in the way a linear primary amine would. That selectivity is occasionally the reason it is specified in a route that has nothing to do with putting a tert-butyl group into the product.

Quality Control & Testing

Every lot is released against a batch-specific Certificate of Analysis. The methods behind the numbers are standard across the industry, and we are happy to share them or to work to your own in-house test protocol.

• Assay and amine distribution — gas chromatography, which resolves tert-butylamine from the other isomers and quantifies di-tert-butylamine and residual ammonia.
• Water content — Karl Fischer titration. This is the critical specification for sulfenamide manufacture, where the sulfur intermediates hydrolyse readily.
• Residual hydrocarbons and alcohol — headspace GC for isobutylene and tert-butanol carried over from the amination route, which matter in pharmaceutical service.
• Distillation range — a fast, revealing check. A broadened range usually signals light ends or moisture before any instrument confirms it.
• Colour — APHA / Hazen against a standard. Colour drift signals air ingress or metal contamination.
• Metals and residue — iron and evaporation residue, both of which matter in pharmaceutical and fine chemical service.

Common Process Problems & Likely Causes

When tert-butylamine misbehaves in a plant, the cause is usually one of a short list of things. This table is the shortcut our technical desk works through before anyone opens a complaint file.

Packaging, Storage & Shipping

• Standard packing. 140 kg net in lined steel drums rated for the vapour pressure, with 1000 L IBCs for larger users.
• Bulk packing. Road tankers and ISO tank containers for rubber chemical plants and continuous processes.
• Inert blanketing. Nitrogen-blanketed at fill where the grade and end use call for it, to protect colour and water specification in storage.
• Storage. Cool, shaded, well-ventilated and bunded area away from heat, ignition sources, oxidisers and acids, with containers kept tightly closed.
• Materials of construction. Stainless steel, carbon steel or suitable lined vessels. Avoid copper, brass, bronze, aluminium and mercury, all of which are attacked by amines.
• Shelf life. Typically 12 months in unopened original packing under those conditions. Beyond that, re-test rather than assume.
• Temperature and pressure. With a boiling point near 45 °C the vapour pressure is substantial at summer ambient. Shaded or temperature-controlled storage is sensible, and containers should be opened cool.
• Transport classification. Typically shipped under UN 2733, Amines, flammable, corrosive, n.o.s., Class 3 with subsidiary risk 8, Packing Group II. Confirm the entry and packing group against the current SDS and the shipper's declaration for your destination and mode.
• Container loading. Palletised and secured for FCL; LCL consolidation and tank arrangements available by volume.

Hazards & Safe Handling

tert-Butylamine is highly flammable and corrosive, and must be handled by trained personnel under a proper risk assessment. The classifications below are indicative — the current SDS supplied with your consignment is the governing document.

• Exposure control. Handle in a closed system or under local exhaust ventilation. The flash point is below ambient, so the vapour space above the liquid sits in the flammable range in normal storage.
• PPE. Chemical-resistant gloves, chemical goggles and face shield, chemical-resistant clothing, and respiratory protection suited to the task.
• Ignition control. Vapours are heavier than air, travel along the ground to a distant ignition source and flash back. Bonded, earthed and explosion-proof equipment, and no ignition sources in the zone.
• Incompatibilities. Strong oxidising agents, strong acids, acid chlorides, nitrites, mercury, and copper, brass, bronze and aluminium equipment.
• Spill response. Eliminate ignition sources and ventilate. Contain, absorb with inert non-combustible material and collect in a labelled closed container. Do not wash to drain.
• Environment. Do not allow to enter drains, surface water or groundwater. Dispose through a licensed chemical waste contractor.
• Fire. Highly flammable. Use alcohol-resistant foam, dry chemical or carbon dioxide; cool exposed containers with water spray. Decomposition releases nitrogen oxides — use self-contained breathing apparatus.
• First aid. Move to fresh air, remove contaminated clothing immediately, wash skin with plenty of water, flush eyes for at least 15 minutes, and seek medical attention with the SDS to hand.
• Pressure awareness. With a boiling point near 45 °C, containers develop pressure in warm conditions. Open cool, relieve pressure in a controlled way, and never apply heat to a sealed container.

Regulatory & Compliance Notes

tert-Butylamine is a long-established industrial chemical and is listed on the major national chemical inventories. Because obligations differ by territory, volume and use, the notes below are orientation rather than legal advice — confirm your own position with your regulatory adviser before importing.

• Inventory status. Listed on the principal chemical inventories in the major importing regions. Ask us for the inventory confirmation relevant to your destination country.
• Isomer identity. The four butylamine isomers are separate substances with separate CAS numbers and separate registrations. Make sure your import documentation, inventory listing and end-use approval all name the isomer you are actually buying.
• Import registration. Several territories require the importer to hold a registration or notification before a consignment lands. Start that process early — it is the most common cause of delay at destination.
• Hazard communication. Supplied with an SDS compliant with the format applicable to your region, and labelled in line with the GHS classification for the product.
• Dangerous goods. Typically UN 2733, Amines, flammable, corrosive, n.o.s., Class 3 with subsidiary risk 8, Packing Group II. Because this is a generic entry, confirm the classification against the current SDS; declarations prepared for IMDG (sea) or IATA (air) as appropriate.
• Workplace exposure. Occupational exposure limits apply in most jurisdictions. Set your controls against the limit in force where the material will be handled.

We Supply TBA Worldwide

Chelora Chemicals is a supplier and export partner, not a single-plant trader. We ship tert-Butylamine from India to customers across Asia, Europe, the Middle East, Africa, and North and South America, handling the export documentation, dangerous-goods paperwork and freight so the material arrives ready to use.

• Incoterms. EXW, FOB, CIF, CFR and DAP quoted to suit your purchasing terms and freight arrangements.
• Ports. Regular shipments through Nhava Sheva (JNPT) and Mundra, with other Indian ports arranged where it suits the routing.
• Documentation. Commercial invoice, packing list, certificate of origin, COA, SDS and dangerous-goods declaration issued as a complete set.
• Flexible volumes. A single drum for laboratory qualification, through LCL consolidations, up to repeat full loads on a supply contract.
• Supply continuity. Because we are independent of any one producer, a plant turnaround or a shipping disruption at one source does not have to become your stock-out.

Buying TBA from Chelora

We are an independent sourcing and supply partner. For tert-butylamine that means matching the grade to the application — a low-water cut for sulfenamide manufacture, a low-residual-hydrocarbon grade for pharmaceutical use — rather than selling whatever happens to be in the tank. The two look identical on an assay and behave quite differently in a reactor.

• Documentation on every lot. Batch-specific COA, current SDS and TDS issued with the consignment, not weeks afterward.
• Samples before commitment. Trial quantities for process qualification ahead of a commercial order.
• Quantities. From a single 140 kg drum through to repeat tank loads on contract supply.
• Export experience. Dangerous-goods documentation, packing and labelling handled for sea and road freight to any destination.
• Technical support. Direct access to people who know the chemistry, for questions on water specification, production route or pressure handling.
• Related intermediates. n-, iso- and sec-butylamine, isopropylamine, cyclohexylamine and the wider rubber chemical amine range from one supplier.

How ordering works

• Send the enquiry. Product, grade or specification, quantity, destination port and the Incoterm you buy on. If you have a spec sheet, attach it — it saves a round trip.
• We quote. Price, lead time, packing and a sample COA, normally within one working day.
• Sample and qualify. For first orders or critical applications, we send a trial quantity so your lab can sign off before you commit.
• Confirm the order. Proforma invoice issued; payment terms agreed against the volume and the relationship.
• Production and QC. Material allocated and released against a batch-specific COA, with a pre-shipment sample where the application calls for it.
• Ship and document. Packed, labelled and loaded with the full export and dangerous-goods document set, and tracked through to arrival.

Related Amines & Intermediates

Buyers of tert-butylamine usually source several of these alongside it. Consolidating them on one order cuts freight cost and gives you a single point of contact for documentation.