5-Methyl-2-hexanone emerged from the broader family of methylated ketones that chemists actively explored for their roles in synthesis and industry throughout the early and mid-20th century. Its discovery and isolation built upon the understanding gained from simpler, related compounds such as methyl isobutyl ketone. Industrial interest in this molecule ramped up as the sector searched for new solvents, intermediates, and building blocks capable of handling demanding processes. Large-scale production began once companies recognized its unique solvent profile, particularly for resins and certain coating applications, laying the foundation for further innovation and practical use.
5-Methyl-2-hexanone stands out in the ketone family thanks to its branched structure and moderate polarity. Its liquid state, clear color, and strong odor remind me of many solvent chemicals commonly sitting on the shelf in any process lab. You don’t see this compound in everyday consumer goods, but people lucky enough to work with specialty chemicals or coatings run into it on product data sheets and handling guides. Many companies have tapped into its utility, fitting this ketone into solvent blends, chemical synthesis, and even as a raw material for certain fragrances.
This compound boils at about 135–140°C, a range that works well for mid-temperature applications. It has a density slightly below water, so spills float, creating clear hazards in labs or factories. Solubility sits low in water but high for organic liquids, making it a reliable choice for mixing in non-polar solutions. The molecule packs a branched chain, making its volatility and evaporation rate lower than its straight-chain relatives. Its methyl group on the hexanone skeleton weakens hydrogen-bonding ability, which affects both solubility parameters and interactions with other chemicals.
Producers deliver 5-Methyl-2-hexanone with specifications calling for purity, moisture, and a contaminant profile that matches the target industry—whether for synthesis or as a blending solvent. Labels clearly state the CAS number, batch information, flammability, and recommended storage temperature. Drums used get an inner lining or a compatible plastic to prevent degradation or unwanted reaction with the walls. Packing firms use color-coded symbols to warn handlers about fire risks, inhalation dangers, and proper spill responses.
Industrial routes rely on the catalytic condensation of 2-pentanone or analogues with methylating agents. This process needs careful temperature control, active mixing, and a water-exclusion strategy, considering the hydrolysis risk during intermediate stages. Facilities using continuous reactors get higher yields with steady-state operation, and purification ends with fractional distillation. Research facilities sometimes adjust feed compositions to optimize product streams and minimize by-product waste, an ongoing goal for any chemical process engineer wanting good atom economy.
In the lab, 5-Methyl-2-hexanone handles classic nucleophilic additions, especially under strong basic or acid conditions. Reduction yields the corresponding alcohol, which gets used in further functionalizations. It performs well in aldol-type reactions, where its methyl branching influences product selectivity and intermediate stability. Halogenation at the alpha carbon works, giving intermediates for agrochemical or pharmaceutical development. The branched structure adds some steric hindrance, delaying or diverting certain transformations and making reaction planning a careful process.
Different suppliers and regulatory documents refer to 5-Methyl-2-hexanone using names like 2-Hexoanone, 5-methyl, or more consumer-facing terms like Isoheptanone. Sometimes it’s listed as methyl isohexyl ketone or 5-methylhexan-2-one. Trade catalogs lean on these synonyms to reach buyers in coatings, adhesives, or specialty intermediates markets, an important step for harmonizing data in global commerce databases and regulatory filings.
Direct contact with this ketone irritates skin and eyes, and breathing in the vapors brings on dizziness or headaches. Fire safety officers train staff to use explosion-proof pumps and grounded containers since the compound carries a real vapor ignition risk. Material safety data sheets describe emergency procedures, including suitable extinguishing agents and first-aid responses, and remind everyone to use gloves, goggles, and well-ventilated spaces. Frequent training and up-to-date regulatory compliance checks reduce accident risks, especially in plants with a constant flow of hazardous liquids.
Industrial clients rely on 5-Methyl-2-hexanone mostly as a solvent for paints, inks, coatings, and certain resin systems. Formulators prefer it because of its evaporation profile—neither too fast nor too slow for many film formation requirements. Some fragrance chemists value it as a precursor in synthesizing complex aroma compounds. In smaller specialty labs, it pops up in research on new chemical reactions or as a controlled intermediate for custom syntheses. The compound also finds use in cleaning agents for electronics or metal fabrication, where controlled dissolving power matters more than consumer safety or pleasant odor.
Current R&D activity explores catalytic processes to make the compound more efficiently, aiming to cut production costs while limiting unwanted by-products. Green chemistry groups try out alternative bio-based routes from renewable alcohols or ketone precursors. Researchers watching downstream processing search for methods to separate, recycle, or even recover the ketone from process streams, keeping sustainability in focus. Academic work dissects the effects of its branched structure on reaction dynamics and product selectivity in multi-step syntheses. Many teams publish performance data on new uses in coatings and polymers where its volatility lets end-users fine-tune product behavior for specific conditions.
Scientific work shows moderate to high acute toxicity if inhaled or ingested in concentrated form. Long-term exposure raises the risk for kidney or liver impairment, highlighted by animal studies running at exposure levels outside normal workplace air concentrations. Investigation continues into neurological effects, with some lines of evidence connecting repeated inhalation to cognitive or nerve function changes. Regulators ask producers to disclose comprehensive toxicological data, and researchers run comparative tests with related ketones to benchmark occupational health risks. Calls for more granular longitudinal studies emphasize workplace and environmental health, especially in facilities using the chemical at scale.
Interest in 5-Methyl-2-hexanone will likely track growth in high-performance coating markets and specialty synthesis. Regulatory pressure on volatile organic compounds pushes laboratories and factories to seek substitutes or greener processes, challenging manufacturers to innovate with more sustainable feedstocks. Advances in catalysis and process intensification offer hope for energy and resource savings across the production chain. As collaborative research builds more thorough toxicity and environmental fate profiles, companies will better understand safe application settings as well as disposal or recycling strategies. New market entrants may leverage digital labeling and real-time hazard communication tools, helping frontline workers make smarter day-to-day handling decisions.
5-Methyl-2-hexanone, a colorless liquid with a recognizable odor, often turns up in places folks don’t expect. Factories rely on it mainly as a solvent. Paints and coatings manufacturers want a solvent that can blend different ingredients well, help paints dry at the right speed, and achieve the even finish that keeps customers happy. 5-Methyl-2-hexanone helps with all those things. In printing inks and varnishes, its properties make it easier to control thickness and drying time, which sharpens the final look of the product. The coating on a new appliance or the crisp lines on high-quality printed packages owe a lot to how well this compound performs.
The grip that 5-Methyl-2-hexanone has in industry is based on its ability to dissolve complicated compounds. Plastics, adhesives, and sealants each need specific formulas to deliver results. This solvent manages heavy lifting in those blends, supporting everything from the glue that holds shoes together to insulation that keeps houses energy-efficient. While working as a chemist in a paints research lab, I leaned on 5-Methyl-2-hexanone to test new resin blends. The chemical’s performance saved us time and cut costs by minimizing the trial-and-error phase. When you get consistent results like this, companies avoid the hassle of reworking batches, which reduces waste.
Factories and labs that use 5-Methyl-2-hexanone don’t just pour it into a vat and forget about it. Exposure brings health risks. Breathing in too much vapor can irritate eyes, noses, and throats. Prolonged or repeated exposure raises bigger concerns, including effects on the nervous system. The National Institute for Occupational Safety and Health (NIOSH) and the Occupational Safety and Health Administration (OSHA) set clear rules about air quality and personal protection for people handling this compound. Ventilation systems and protective masks might feel like background details, but I’ve seen seasoned technicians insist on them for good reason. A moment of carelessness can end careers.
Companies always hear that greener chemistry is the future. 5-Methyl-2-hexanone isn’t considered environmentally safe in large quantities. Spills or run-off in water can harm aquatic life, and improper disposal pollutes groundwater. Paint manufacturers and plastics engineers look for alternative solvents with lower toxicity and easier handling. Some have shifted to water-based systems, which cut back on volatile organic compounds altogether. These changes add up. Communities near manufacturing centers benefit from fewer emissions, and plant workers report fewer headaches or skin issues.
Quality control teams watch for signs that solvents stray from safety standards. Reliable suppliers take pride in purity and consistency, using lab tests to catch anything off. Many businesses depend on that trust, especially when complaints or recalls can do real damage. Good science, sensible safety policies, and listening to workers have already improved how risky chemicals are handled. If companies stay honest about what’s in use and push for safer alternatives, folks at work and at home will see more benefits with fewer risks down the road.
5-Methyl-2-hexanone packs a punch as a solvent. Its sharp odor hits you fast, and with any direct contact, there’s no doubt this substance finds a way through gloves or skin if you’re not careful. From my time on the plant floor, it’s clear one slip-up with these potent ketones leads to headaches, burning eyes, or worse respiratory issues. The risk grows around careless spills and open containers, as fumes don’t just linger — they fill up even big spaces before you know it.
Walking into a lab or warehouse, the difference between trouble and routine often hangs on the right protective gear. Nitrile gloves stand up best against 5-Methyl-2-hexanone. Latex just doesn’t cut it — I’ve watched discoloration and thinning happen before my eyes. Long sleeves, chemical goggles, and a face shield settle any doubts about splashback. Proper work shoes keep toes safe from drips that land fast without warning.
Strong ventilation makes a bigger difference than folks realize. In one cramped shop, a basic fan barely dented the smell or sting after a spill. Switching to well-placed exhaust hoods and keeping windows cracked cut headaches and watered eyes, and the air actually tasted clean. Fresh air works best, but mechanical systems pick up the rest. Relying on open doors alone doesn’t do the trick in winter or on rainy days.
Leaving solvent-soaked rags in the corner risks ignition and ruins the air quality. Safe procedures, like locking up the chemical in fire-resistant cabinets and labeling every bottle, mean no surprise accidents during shift changes. Cleaning up spills right away, with the right absorbent material, prevents both slips and long-term skin problems. I’ve seen careless storage eat right through a shelf over time, so checking containers for cracks turns into a habit you can’t skip.
Anyone who’s handled solvents long enough knows how faint headaches and strange fatigue turn up after a sloppy workday. The CDC and NIOSH lay out clear limits on what workers should breathe in each day, and those numbers exist for good reason. Regular breaks outdoors, handwashing with soap instead of rough solvents, and reporting symptoms early keep people healthy in the long run. Firing up a cigarette or vaping around an open drum takes one near-miss to understand just how quickly vapors can catch fire.
No chemical label or warning poster beats a hands-on training session. New hires learn to respect the solvent fast after one timed emergency drill. Emergency eyewash stations, shower units, and clean-up kits hang where they’re needed most, not hidden in the back of the building. Simple routines, like checking for leaks at the start and end of each shift, reinforce good habits in every worker — not just the safety manager.
Real safety means planning ahead and respecting experience. With 5-Methyl-2-hexanone, small steps — fresh gloves, checking the hood, strict storage, and solid cleanup — save time, money, and headaches. People stay healthy when gear goes on first and corners never get cut. Everyone on the work floor, from the greenest hire to the old hands, makes the difference between a rough day and a safe, productive shift.
Anyone who’s stood in a warehouse with solvent fumes creeping up their nose knows that labels and factsheets don’t capture the real-world impact of chemicals like 5-Methyl-2-hexanone. They usually just say “irritant.” Years of working in environments where industrial solvents get used remind me that health and safety matter most once something goes wrong—customers call in with headaches, and techs complain about burning eyes. That’s real exposure, not just a line in a catalogue.
Experience teaches fast that 5-Methyl-2-hexanone has punchy vapors. Acute exposure leads to dizziness, fatigue, and nausea, which are classic symptoms for volatile ketones. The U.S. National Library of Medicine and NIOSH both point out that the substance irritates skin and eyes. Inhaling high amounts over time means more than just discomfort; animal studies show kidney and liver damage is possible after repeated exposure to similar solvents. People in manufacturing or maintenance crews share stories not just of itchy eyes, but real struggles with coughing and fatigue after hours spent in spaces with poor ventilation.
Chronic health risks matter even more. Chemicals like this can sneak up on workers, sending folks home feeling worn out, dehydrated, or with headaches that stick around. I’ve known co-workers who shrugged off symptoms for months, only to find out they had developed sensitivity to chemical vapors.
Spilling a few liters in a workshop didn’t seem like a big deal to some. Then fish started popping up dead downstream. 5-Methyl-2-hexanone evaporates quickly, contaminates groundwater, and lingers in soil. Studies from the EPA show solvent run-offs have wiped out local aquatic life. Unchecked, it pollutes rivers and threatens drinking water. In my hometown, years ago, a careless storage drum leaked and made the local news once the wells tested positive for contaminants.
Workplace habits build up over years, but bad habits haunt longer. Proper gloves, goggles, exhaust venting—standard stuff, often skipped during busy weeks. OSHA has limits for these solvents for good reason. Enforcement works best when people understand the stakes. Factories I’ve visited run air sensors and train their crews to recognize trouble. Paint shops run proper extractor fans and share out respirators, not just as a box-tick, but because nobody wants to see a friend come down with “solvent flu.”
Disposal isn’t just about following protocol; it’s about making sure people and wildlife don’t pay the price. Municipal waste treatment facilities often can’t break down these chemicals, so improper disposal leads to bioaccumulation and ecosystem disruption. Regulations might seem strict, but wildlife loss reminds us why.
Switching to safer substitutes and engineering controls makes a difference. Many companies opt for less volatile or less toxic alternatives when they can—sometimes green chemistry pays off in the long run with fewer sick days and wildlife deaths. Local governments run hazardous waste pickups and clamp down on illegal dumping, but keeping watch only goes so far.
5-Methyl-2-hexanone serves a purpose in industry, but daily use carries real risks. Experience on the shop floor and lessons from communities prove that vigilance and respect for safety save lives—not just for workers in the line of fire, but for neighbors and ecosystems that can’t speak up for themselves.
Some people call 5-Methyl-2-hexanone by another name: methyl isoamyl ketone. If you get close to it, you'll notice a pretty strong odor. The liquid normally looks colorless and flows with a consistency much like water. Its boiling point lands around 142°C—higher than plain water but nowhere near the reach of heavier industrial solvents. That tells you it needs a fair amount of heat to vaporize, but in the real world, plenty of hot environments can make that happen easily. It freezes at about -70°C, so you’re unlikely to see it as a solid anywhere outside a lab freezer.
The density doesn’t stand out much—on average, about 0.81 grams per cubic centimeter. It floats on water, which matters if you think about accidental spills. Since it doesn't dissolve well in water, it tends to form its own layer, which can pose an interesting challenge in terms of cleanup and containment.
Let’s step into the reactivity room. As a ketone, 5-Methyl-2-hexanone holds a carbonyl group in its structure, making it decently reactive with substances like strong acids or oxidizers. There’s nothing explosive about it under normal conditions, but it catches fire real quick. The flash point clocks in at around 40°C, which puts it right in the range where one bad day in a hot warehouse leads to a serious fire risk.
On the stability front, it behaves pretty well under ordinary storage, provided you keep it away from the usual troublemakers—no direct sunlight, no high heat, no storing with strong acids or bases. If it finds itself with strong oxidizing agents, all bets are off. These sorts of accidents don’t just pose chemical risks; folks have lost buildings and much worse from not respecting solvent storage rules.
Industries use this solvent for making coatings, adhesives, and sometimes in cleaning products. That means a lot of people, from factory workers to lab techs, interact with it. It’s less toxic than some other solvents, but inhaling the vapors or getting it on your skin for long stretches brings health risks—think headaches, dizziness, or skin irritation. I remember one summer doing temp work in a shop where ventilation was more of a window held open by a broken chair leg. Within an hour, heads got foggy and hands tingled. Nobody deserves that, and it always comes down to respect for what these chemicals can do.
The safety data isn’t just bureaucracy; it exists because accidents happen. Air monitoring, gloves, face shields, and those battered old fume hoods actually protect people. On a bigger scale, spills matter too. Because 5-Methyl-2-hexanone floats and resists water, a dump into a stream can cause damage to aquatic life, with animals exposed to solvent layers at the surface. The solution goes beyond a company’s fence line—local communities and emergency responders need information and practice for dealing with chemical spills.
Every workspace using this ketone needs proper training and real supplies on hand—not just dusty fire extinguishers but working ventilation, labeled containers, and basic spill kits. Companies should buy less hazardous alternatives if possible, and switch up processes to reduce how much volatile chemical floats in the air. Reliable record-keeping keeps authorities and workers informed about what’s stored nearby, while emergency response plans connected to local fire and hazmat crews turn would-be disasters into manageable inconveniences. Sometimes the best improvements start with conversations—between workers, between companies and communities—about what needs to change to keep people and the environment safe.
Anyone who has worked around strong solvents knows how one spill can turn a quiet afternoon into a safety scramble. 5-Methyl-2-hexanone, a colorless liquid with a powerful scent, plays an important role in industry but doesn’t mix well with carelessness. Flammable vapors and skin irritation don’t just threaten equipment; they threaten people. Storing this chemical means keeping risk out of the room. Use stainless steel or approved polyethylene containers with tightly sealed lids. Never leave the cap loose, even for a moment. Flammable liquids need a ventilated, fireproof storage cabinet—not a shelf next to cleaning supplies or open light fixtures.
Heat speeds up chemical reactions, so look for a cool, dry spot away from sunlight and radiators. Humidity stirs up trouble, making leaks more likely and containers more prone to rust. If you’ve got a busy shop or lab, make it a practice to label every bottle. I’ve seen mix-ups with far less dangerous liquids blow up into costly mistakes. Keep an updated inventory so you don’t buy more than you actually use. Routine checks catch cracks, bulging seals, and mystery drips before they turn into an emergency.
Breathing in fumes never did anyone any good. Storage areas should have mechanical ventilation, even if you don’t notice any smell right away. One whiff near an open bottle is enough to remind you why a chemical-resistant mask and gloves matter. Goggles come with a reason—spilled solvent leaves burns and rashes that last longer than a glove change.
Pouring leftover solvent into a sink used to be a common move. Rules have changed for good reason—5-Methyl-2-hexanone leaks into groundwater or seeps into storm drains, affecting more than just the building. Local regulations require hazardous waste pickup for a reason. For shops without a chemical disposal contract, most counties now offer drop-off events or approved collection centers. Always keep waste solvents in their original packaging if possible, and never mix them with household trash. Mark the bottles clearly with their contents and hazards.
I’ve seen coworkers dismiss disposal rules until an inspector walks through the door or a child gets exposed to something they shouldn’t. Take the extra minute for a call to local waste services—ask about pickup days and required paperwork. Don’t rely on memories from a safety class ten years back; protocols change. Never burn, bury, or evaporate solvents outdoors. Air pollution and contaminated soil don’t look much different than a clean garden at first glance—until water tests come back with bad news.
No job site thrives on guesswork. Make safety talks a real part of the workweek, not just a checkbox on a hiring packet. Share stories about close calls; people pay more attention to hard lessons over dry policy manuals. Keep spill kits stocked with absorbent pads and neutralizing agents. Make sure new hires can actually locate emergency showers, eyewash stations, and fire extinguishers. No one plans for an accident—they’re always unexpected until they land on your doorstep.
Managing chemicals isn’t only about rules and paperwork. It’s about keeping people safe and community groundwater clean. Each step—storage, ventilation, disposal—protects more than just a paycheck. It protects families, coworkers, and the environment that everyone shares.
| Names | |
| Preferred IUPAC name | 3-Methylhexan-2-one |
| Other names |
Methyl isoamyl ketone
MIAK Isopentyl methyl ketone |
| Pronunciation | /ˈfaɪˈmɛθəl tuː ˈhɛk.səˌnoʊn/ |
| Identifiers | |
| CAS Number | 110-12-3 |
| Beilstein Reference | 803478 |
| ChEBI | CHEBI:132785 |
| ChEMBL | CHEMBL155715 |
| ChemSpider | 7066 |
| DrugBank | DB02170 |
| ECHA InfoCard | 100.017.859 |
| EC Number | 203-684-2 |
| Gmelin Reference | 78974 |
| KEGG | C19624 |
| MeSH | D008871 |
| PubChem CID | 8059 |
| RTECS number | SA8575000 |
| UNII | U077U8I5TC |
| UN number | UN1235 |
| Properties | |
| Chemical formula | C7H14O |
| Molar mass | 114.19 g/mol |
| Appearance | Colorless liquid |
| Odor | sweet |
| Density | 0. Eight two six g/mL at 25 °C (lit.) |
| Solubility in water | slightly soluble |
| log P | 1.98 |
| Vapor pressure | 1.8 mmHg (20°C) |
| Acidity (pKa) | pKa ≈ 20 |
| Basicity (pKb) | 5.18 |
| Magnetic susceptibility (χ) | -7.62 × 10⁻⁶ cm³/mol |
| Refractive index (nD) | nD 1.410 |
| Viscosity | 1.02 mPa·s (25 °C) |
| Dipole moment | 2.75 D |
| Thermochemistry | |
| Std molar entropy (S⦵298) | S⦵298 = 340.6 J·mol⁻¹·K⁻¹ |
| Std enthalpy of formation (ΔfH⦵298) | -295.0 kJ/mol |
| Std enthalpy of combustion (ΔcH⦵298) | -3877.0 kJ/mol |
| Pharmacology | |
| ATC code | V04CX |
| Hazards | |
| GHS labelling | GHS02, GHS07 |
| Pictograms | GHS02, GHS07 |
| Signal word | Warning |
| Hazard statements | H226, H315, H319, H335 |
| Precautionary statements | P210, P243, P261, P271, P280, P301+P312, P303+P361+P353, P304+P340, P305+P351+P338, P312, P337+P313, P370+P378, P403+P235, P501 |
| NFPA 704 (fire diamond) | 1-2-0 |
| Flash point | Flash point: 51°C |
| Autoignition temperature | 460°C |
| Explosive limits | 1.1–7% |
| Lethal dose or concentration | LD50 oral rat 2080 mg/kg |
| LD50 (median dose) | LD50 (oral, rat): 2080 mg/kg |
| NIOSH | MG8225000 |
| PEL (Permissible) | PEL: 100 ppm (410 mg/m³) |
| REL (Recommended) | 28 mg/m3 |
| IDLH (Immediate danger) | 100 ppm |
