Diisopropylamine CAS 108-18-9

What is Diisopropylamine?

Diisopropylamine is a sterically hindered secondary amine — two isopropyl groups flanking a single N-H, [(CH₃)₂CH]₂NH. Those two branched groups crowd the nitrogen from both sides, and that crowding is the entire reason the molecule has the market it does.

It is a clear, colourless liquid boiling at about 84 °C, with a strong fishy and ammoniacal odour. The flash point sits near −6 °C, so it is highly flammable and the vapour space above the liquid is in the flammable range in ordinary storage. Unlike the lower amines it has only limited solubility in water — roughly a tenth by weight at room temperature — which makes aqueous work-ups behave quite differently.

Chemically it is a strong base and a poor nucleophile. That combination is unusual and extremely useful: it can remove a proton without attacking a carbonyl or an alkyl halide, which is exactly what a synthetic chemist wants from a base. Its lithium salt, lithium diisopropylamide, is one of the most widely used strong bases in organic synthesis for precisely this reason.

Commercially, diisopropylamine divides between two worlds. In agriculture it supplies the diisopropylamino group to thiocarbamate herbicides. In fine chemicals and pharmaceuticals it is bought as a reagent — the precursor to lithium diisopropylamide and to the hindered tertiary base diisopropylethylamine — rather than as a building block that ends up in the product.

Why diisopropylamine specifically

• Strong base, weak nucleophile. The two isopropyl groups shield the nitrogen, so it deprotonates readily but attacks electrophiles slowly. Few reagents separate those two behaviours as cleanly.
• Precursor to lithium diisopropylamide. Deprotonated with butyllithium it gives LDA, the standard strong, hindered, non-nucleophilic base for enolate chemistry across pharmaceutical and fine chemical synthesis.
• Precursor to Hünig's base. Ethylation gives diisopropylethylamine, the hindered tertiary base used as an acid scavenger where triethylamine would be too nucleophilic.
• Limited water solubility. Unlike the lower amines it partitions into an organic phase, which simplifies recovery and work-up in a way the fully miscible amines do not.

How DIPA is Manufactured

Diisopropylamine is made alongside isopropylamine on the same plant, either by aminating isopropanol or by reductive amination of acetone. The configuration of the reactor and the recycle decides which amine dominates.

• Amination or reductive amination. Isopropanol or acetone is reacted with ammonia and hydrogen over a supported metal catalyst at elevated temperature and pressure, giving an equilibrium mixture of mono- and di-isopropylamine. Steric crowding means the tri- amine barely forms at all, which simplifies the distribution relative to the linear amines.
• Ratio control. A plant configured for the di- product runs a lower ammonia-to-substrate ratio than one making the mono amine, and recycles mono-isopropylamine back to the reactor to push the equilibrium onward.
• Separation. The crude mixture is resolved by fractional distillation with ammonia recovery. Diisopropylamine boils well clear of the mono amine, so it is comparatively straightforward to take to high purity.
• Drying and finishing. The di- cut is dried to specification — azeotropic drying or molecular sieves depending on the grade — and filled into drums, IBCs or tanks, with nitrogen blanketing where water and colour matter.

Typical Commercial Specification

Figures below are representative of standard commercial grade. Low-water grades for organolithium and pharmaceutical service are available — send us the specification you work to and we will quote against it.

Physical & Chemical Properties

Reactivity in practice

Diisopropylamine is bought mainly for what it does rather than for what it becomes. Four roles cover nearly all of its use:

• Lithium diisopropylamide generation. Deprotonation with n-butyllithium gives LDA, a strong, hindered, non-nucleophilic base used to form enolates and carbanions cleanly without competing addition.
• Hindered tertiary base synthesis. Ethylation gives diisopropylethylamine, the acid scavenger of choice where a less hindered base would alkylate or attack the substrate.
• Thiocarbamate formation. Reaction with carbonyl sulphide or thiophosgene chemistry gives the diisopropyl thiocarbamate backbone used in soil-applied herbicides.
• Salt formation and inhibition. Forms stable salts with mineral and organic acids; the nitrite salt has historically been used as a vapour-phase corrosion inhibitor, and other salts appear in petroleum additive packages.

Diisopropylamine vs Other Synthesis Bases

Diisopropylamine is usually chosen against a short list of alternatives, and the choice turns on how hindered the base needs to be and whether an N-H is wanted. Note also the abbreviation clash: DIPA is used for both diisopropylamine and diisopropanolamine, which are entirely different products.

Stated plainly: diethylamine reacts, diisopropylamine deprotonates. Where a secondary amine is wanted to become part of the product, the unhindered one is usually correct; where a strong base is wanted that will not attack the substrate, the hindered one is. And if an enquiry simply says "DIPA", confirm the CAS number before quoting — diisopropanolamine shares the abbreviation and nothing else.

Industries We Supply DIPA To

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

Where DIPA is Used

Diisopropylamine splits between agricultural volume and fine chemical value. These are the end uses our customers buy it for, roughly in order of volume.

As a lithium diisopropylamide precursor

This is the application that makes diisopropylamine a household name in synthetic chemistry. Treated with n-butyllithium at low temperature it gives lithium diisopropylamide, a base strong enough to remove a proton alpha to a carbonyl but far too hindered to add to the carbonyl itself. That selectivity is what allows clean enolate formation and controlled alkylation. Water is the critical specification here: it destroys the organolithium reagent stoichiometrically, so a low-water grade is the realistic requirement and many users dry further on site.

In thiocarbamate herbicide manufacture

The diisopropylamino group appears in soil-applied thiocarbamate herbicides used mainly in cereals and other broad-acre crops. The chemistry runs through carbonyl sulphide or thiophosgene equivalents, and plants running these actives care about isopropylamine carry-over, since a primary amine reacts twice and gives a bridged by-product.

As a precursor to Hünig's base

Ethylation of diisopropylamine gives diisopropylethylamine, a tertiary amine so crowded that it will scavenge acid without competing as a nucleophile at all. It is the standard base in peptide coupling and in acylations where triethylamine would attack the activated intermediate. Fine chemical customers often buy the secondary amine and make the tertiary base in house.

In corrosion inhibition

Diisopropylamine salts have a long history in corrosion protection, including as vapour-phase inhibitors that sublime into the headspace of sealed packaging to protect metal parts in transit. Note that the nitrite salt route brings a secondary amine and a nitrosating agent into the same system, which needs a deliberate nitrosamine risk assessment rather than an assumption.

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 di- and mono-isopropylamine and quantifies residual ammonia, acetone and isopropanol in one run.
• Water content — Karl Fischer titration, and the single most important specification for anyone generating an organolithium base from it.
• Distillation range — a fast, revealing check. A broadened range usually signals mono amine or moisture carry-over before any instrument confirms it.
• Colour — APHA / Hazen against a standard. Colour drift signals air ingress or metal contamination.
• Metals — iron in particular, since it catalyses discolouration and can interfere with organometallic chemistry.
• Non-volatile residue — evaporation residue, a quick check for carry-over of heavies from the column train.

Common Process Problems & Likely Causes

When diisopropylamine 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. 160 kg net in lined steel or HDPE drums, with 1000 L IBCs for larger users.
• Bulk packing. Road tankers and ISO tank containers for continuous processes.
• Inert blanketing. Nitrogen-blanketed at fill where the grade and end use call for it. For low-water grades this is not optional — an unblanketed drum picks up moisture from the headspace every time it is opened.
• Storage. Cool, dry, 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.
• Transport classification. UN 1158, Diisopropylamine, Class 3 flammable liquid with subsidiary risk 8 corrosive, Packing Group II — shipped with full dangerous-goods documentation.
• Container loading. Palletised and secured for FCL; LCL consolidation and tank arrangements available by volume.

Hazards & Safe Handling

Diisopropylamine 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 to a distant ignition source and flash back. Bonded, earthed and explosion-proof equipment, and no ignition sources in the zone.
• Organolithium work. Where the amine is used to generate an organolithium base, the hazards of the butyllithium reagent — pyrophoricity and violent reaction with water — govern the operation. Design the procedure around those, not around the amine.
• 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.
• 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.

Regulatory & Compliance Notes

Diisopropylamine 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.
• Nitrosamine awareness. Secondary amines can form nitrosamines in the presence of nitrosating agents. Where your process or product could bring the two together, build that into your risk assessment and keep nitrite sources out of the handling area. This is a standing consideration for every secondary amine, not a property of any particular lot.
• 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. UN 1158, Class 3 with subsidiary risk 8, Packing Group II. Declarations prepared for IMDG (sea) or IATA (air) as appropriate to the mode.
• 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 DIPA Worldwide

Chelora Chemicals is a supplier and export partner, not a single-plant trader. We ship Diisopropylamine 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 DIPA from Chelora

We are an independent sourcing and supply partner. For diisopropylamine that means matching the water specification to the application — standard grade for herbicide and inhibitor work, a genuinely dry grade for organolithium chemistry — and confirming which DIPA the enquiry actually means before quoting.

• 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 160 kg drum through to tank loads and ongoing 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, blanketing or materials compatibility.
• Related intermediates. Isopropylamine, diethylamine, triethylamine, di-n-butylamine and the wider 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 diisopropylamine 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.