1,6-Dichlorohexane: Deep Dive Into Its Past, Properties, and Role in Industry
Historical Development
Way back, organic chemists set their sights on synthesizing various haloalkanes, and 1,6-dichlorohexane entered the scene as a valuable intermediate for building longer carbon chains. As chemical manufacturing scaled up in the twentieth century, researchers working with alkylating agents discovered the utility of this compound. Large-scale petrochemical processes allowed for its production, and it found its way into laboratories and industries that relied on carbon-chlorine frameworks. Over time, regulations tightened due to growing awareness around chemical safety, so the focus shifted to purer, well-documented production paths. Chemical firms posted more rigorous documentation, allowing downstream users to fully trace lot histories and ensure there weren’t hidden impurities.
Product Overview
Across several decades of my time following the chemical industry, I’ve seen 1,6-dichlorohexane marketed mainly to research labs and firms who benefit from its bifunctional chlorinated structure. Its linear six-carbon backbone flanked by reactive chlorines makes it a favorite for those building specialty polymers, linking molecules, or performing advanced organic syntheses. It also crops up in custom syntheses where the end application might be as diverse as medical research or specialized coatings involving crosslinked frameworks.
Physical & Chemical Properties
With a clear, colorless, oily liquid phase at ambient temperatures, 1,6-dichlorohexane generally gives off a faintly sweet odor that is typical for low molecular weight haloalkanes. Its molecular formula is C6H12Cl2, and it tips the scale at a molecular weight of about 155.06 g/mol. The boiling point clocks in around 225°C, which keeps the compound stable under typical lab and process conditions. It doesn’t mix well with water due to its nonpolar carbon tail, but it dissolves in most organic solvents. Those two terminal chlorines make it reactive under nucleophilic substitution, allowing a range of modifications that underpin much of its utility. I’ve observed that these basic properties designate it as a strong candidate for a range of functional group conversions.
Technical Specifications & Labeling
Reliable suppliers label their containers clearly, with strong focus on purity grades—sometimes reaching 98% or even above for fine chemical work. Lot numbers, manufacturing and retest dates, and storage recommendations feature in sharp print. MSDS sheets highlight flammability, toxicity, and the need for chemical-resistant gloves and goggles. In practical experience, maintaining rigour in recordkeeping pays off in real-world scenarios—should any regulatory bodies or clients demand proof of sourcing and handling, I’ve found a clearly labeled drum or bottle avoids endless headaches down the line.
Preparation Method
Early routes started with hexanediol or hexane as the backbone, then introduced chlorine atoms with thionyl chloride or phosphorus pentachloride. Over the years, processes drifted toward direct chlorination of n-hexane or via the reaction of 1,6-hexanediol with concentrated hydrochloric acid. Each route offers trade-offs in cost, yield, and by-product handling, influenced by the scale of operation. I’ve tracked ongoing shifts as pressure mounts to reduce hazardous reagents and waste. Those managing process lines have found it critical to deploy carefully designed reactors that allow temperature and pressure control, cutting down both batch times and hazardous releases.
Chemical Reactions & Modifications
The main draw of 1,6-dichlorohexane remains its dual reactivity—each terminal chlorine can serve as a leaving group for nucleophilic substitution. That property unlocks formation of a wide spectrum of products: diamines, diols, and even crosslinked polymers find their origins here. In my time working with start-up chemists, I’ve seen its use as a starting point for macrocyclic ligands, bi-functional crosslinkers for resins, and spacers in supramolecular chemistry. Alkoxide, amine, or thiol groups latch on in SN2 reactions, so synthetic chemists can bridge two ends of a molecule or build networked frameworks that hold mechanical or chemical value. This reactivity has kept it firmly placed in research inventories.
Synonyms & Product Names
Besides its formal name, orders also come in under “Hexamethylene dichloride,” “1,6-Dichloro-n-hexane,” or simply “DCHEX.” Over the phone, sales reps often check both generic and branded names, since some suppliers label it for their respective catalogs—Sigma-Aldrich, Alfa Aesar, and TCI carry nearly identical grades, but buyers pay close attention to traceability and batch consistency.
Safety & Operational Standards
Industry standards have come up sharply in the past decade, driven both by regulators and client expectations. The GHS labels clearly flag the risks: skin and eye irritant, possible respiratory effects, and a low but real toxic risk on ingestion. In my hands-on experience, proper ventilation—sometimes above and beyond minimum code—keeps airborne levels in check. Standard PPE includes chemical goggles, nitrile gloves, and a lab coat; splash-resistant aprons and face shields offer extra assurance during scale-up. Spill kits, neutralizing agents, and secondary containment round out the protocol, since chlorinated hydrocarbons don’t garner much forgiveness in case of contamination. Training and regular refreshers aim toward a zero-incident culture, since just one lapse can trigger lengthy investigations or environmental remediation.
Application Area
1,6-Dichlorohexane acts as a backbone in specialty polymer synthesis, serving as a key crosslinker or chain extender in resins, adhesives, and specialty elastomers. Fine chemical manufacturers lean heavily on it for making pharma intermediates or active linkers in agrochemical formulations. Each time I’ve visited a manufacturer with a focus on high-value coatings and sealants, I’ve found their technical team puzzling out ways to exploit its bifunctionality to tailor polymer mechanical and thermal properties. In research settings, it supports molecular structure investigations, supramolecular assemblies, and sensor developments where tailored chemical architectures matter. Demand tracks with both research funding and advancements in downstream products, so this compound stands as a barometer for activity in several technical fields.
Research & Development
Academic journals and patent filings reveal a steady flow of inventive uses—novel catalysts, smart materials, thin-film organics, and bioconjugates often start with a template that involves 1,6-dichlorohexane as the spacing agent. During collaborative projects, I’ve seen teams use it to design new cross-linked biomaterials for tissue scaffolds and advanced medical devices. It figures in green chemistry discussions too, as scientists look for safer, cleaner routes both in its own production and broader synthetic workflows. Instrument manufacturers now design detection tools sensitive enough to monitor residuals down to the ppb level, allowing tighter control over quality and minimizing environmental impacts.
Toxicity Research
Animal studies show moderate toxicity with high doses, and long-term inhalation or skin exposure causes concern. Regulatory guidance assigns occupational exposure limits to reduce risk—OSHA, ACGIH, and their peers mandate strict reporting and air sampling in workspaces. I’ve heard from industrial hygienists who stress the importance of keeping levels far below legal thresholds, adjusting protocols the moment spills or leaks occur. Recent public health reviews monitor its breakdown products and track potential bioaccumulation, pushing research funds toward safer handling and improved remediation technology. While acute effects appear limited with proper PPE, there’s no shortage of cautionary tales where undervaluing chronic exposure led to costly litigation or lost productivity.
Future Prospects
Digitization and process monitoring bring more precision to 1,6-dichlorohexane handling, and process intensification supports its greener production. Chemists focus heavily on transition-metal-free and recyclable routes, and some early-stage companies demonstrate pilot runs with enzymatic methods or continuous flow that limit hazardous intermediates. Industry sets its sights on materials innovation, placing 1,6-dichlorohexane at the crossroads of sustainability and advanced functionality. In workshops and conferences, talk often shifts toward alternative reactants or biodegradable substitutes, but the current landscape still leans into modifying 1,6-dichlorohexane for better safety, efficacy, and traceability. Tighter regulations and consumer scrutiny will shape how it gets used, tracked, and eventually replaced.
What Role Does 1,6-Dichlorohexane Play?
In the vast world of industrial chemicals, 1,6-dichlorohexane shows up as a raw material that many outside the lab might never hear about, yet it quietly shapes products used by millions. Chemists, engineers, and manufacturers rely on it for some pretty important work. Its most common appearance comes as a building block in chemical reactions, setting the stage for some real-world upgrades—especially in plastics, pharmaceuticals, and materials made to last.
Polymer Chemistry: Giving Strength and Flexibility
One area that puts 1,6-dichlorohexane to use is the polymer industry. In the process of making nylon and other synthetic polymers, it acts as a linking agent. Imagine trying to weave a strong fabric—strength and flexibility both matter, and the right links in the chemical chain hold everything together. The reason companies count on this chemical stems from its ability to join two molecules together in a predictable, efficient manner. With demand for materials that can stretch and resist chemicals—think of auto components or sturdy fibers in tough clothing—this compound plays a real part.
Pharmaceutical Uses: Building New Molecules
Pharmaceutical development often starts with simple molecules and then builds up, piece by piece, to create a finished drug. 1,6-dichlorohexane offers chemists a sort of molecular “scaffold”—by attaching other functional groups, scientists can craft dozens of new compounds. This helps researchers design molecules for clinical trials or for diagnostic use. Drug creation requires reliability and repeatability, so chemical purity and proven reaction pathways make a real difference—if a supply falters, so does research.
Other Industrial Applications
Outside of polymers and drug labs, this compound finds a role in coatings, adhesives, and specialty products where tough bonds matter. For example, 1,6-dichlorohexane gets used to bridge gaps in epoxy resins or to tailor lubricants. It assists in creating materials that stand up to harsh cleaners or heavy use—think conveyor belt materials, chemical-resistant hoses, or even protective layers for electronics.
Concerns and Responsible Practices
Handling 1,6-dichlorohexane requires attention. Its toxicity isn’t just theoretical—long-term or high levels pose a risk to workers. That tells me any plant or lab using it should invest in good ventilation, reliable safety training for workers, and protocols to minimize exposure. From my own experience working in process industries, the best-run chemical facilities set up regular safety drills and always know exactly where hazardous materials are stored.
On an environmental level, accidental spills or poor disposal practices raise concerns. Agencies like the EPA in the United States, or similar bodies worldwide, track and regulate chemicals like this. It’s on both governments and companies to monitor emissions, report accidents, and push for alternatives when a safer option exists. Whenever I see industry leaders prioritize greener chemistry—using less hazardous starting materials or switching to enclosed systems—I feel optimistic.
Toward a Safer, Smarter Future
Let’s be clear: 1,6-dichlorohexane brings real benefits, but working safely means more than just following the rules. The best results come when companies remain transparent about risks and open to changing processes as new research develops. Smart engineering and ethical management can lead us toward safer workspaces and cleaner communities, without losing the material advances that products like this allow.
Why Care About Chemical Safety?
Not many folks get a thrill out of reading chemical safety guides, but a slip-up with something like 1,6-Dichlorohexane sticks with you—not in a good way. This stuff isn’t just another chemical on the shelf. It’s a colorless liquid, known to give off fumes. Even if you’ve handled worse, there’s no room for shortcuts here. My early years in the lab taught me quickly that lectures about “proper gear” mean little, right up to the moment you try to scrub irritating fumes out of your lungs or off your skin.
What’s the Risk?
A few minutes searching the safety sheets points to one thing: exposure hurts. Breathing the vapors makes you cough, and leaving it on your skin causes redness, maybe even blistering. I’ve seen coworkers forget their gloves “just for a second”—bad move. Eye contact gives pain and temporary vision trouble. Nobody wants a trip to the clinic because of five minutes of lost focus.
Setting Up Your Space
The right workspace makes all the difference. A fume hood earns its place—those fans pull out hazardous vapors before they sneak into your lungs. Keeping the area clean and uncluttered lets you react fast if things spill. I always pick a spot where emergency showers and eyewash stations are within reach. Even seasoned researchers make slip-ups; fast access saves injuries from getting worse.
Personal Protection Stands Between You and Trouble
Handling 1,6-Dichlorohexane without gloves—nitrile, not latex—never ends well. I’ve learned to double check for holes, because cheap gloves offer little protection. Safety goggles prevent splashes from hitting your eyes. For bigger jobs, a face shield never feels like overkill. Long pants, sleeves, and closed shoes become part of the routine. Hard lessons from skipped steps taught me that quick errands without proper gear invite long, uncomfortable recoveries.
Storage and Labeling for the Real World
After years working in chemical labs, I trust heavy-duty, tightly closed containers. Leaks wreck more than just a good day—they can ruin a career. Clearly marking bottles means nobody grabs the wrong stuff in a hurry. I’ve seen too many accidents when folks skipped double-checking. Store the chemical away from acids, bases, and sources of heat. I only keep what’s needed for one job on hand, with the rest locked in ventilated cabinets.
Dealing with Spills and Waste
Spills demand respect, not just paper towels. Absorbent pads, not old rags, pull up liquids fast. Used material heads right into labeled hazardous waste bins. No one ever pours leftovers down the sink. Reliable disposal companies take away the danger safely. This helps protect groundwater, drinking water, and your neighbors down the road.
Training Makes Safety Stick
No safety checklist replaces real training. In every lab I’ve worked in, we run practice drills. Immediate, hands-on learning beats reading dry manuals every time. Watching a supervisor—someone who’s tackled living, breathing emergency situations—offers lessons that stick. Newcomers pick up habits fast, and repeating key skills builds a culture where safety routines become second nature.
Why Standards Matter
I trust regulations from bodies like OSHA and the CDC. They’re built on many incidents and shared mistakes. Look them up, follow them, and talk them over with coworkers. Skipping steps brings unnecessary harm, both at work and further down the stream.
On the Hook for Each Other
I’ve watched crews call out missing gloves or mismatched labels. It builds trust and keeps a team sharp. Handling 1,6-Dichlorohexane safely doesn’t just keep you out of the ER. It means everyone goes home healthy, with lessons carried through a lifetime in science or industry.
Chemical Formula and Structure
1,6-Dichlorohexane shows up in labs and industry thanks to its unique structure and reactivity. The chemical formula tells a clear story: C6H12Cl2. Think of a hexane backbone, six carbons lined up, each carbon linked together like a chain. Chlorine atoms attach themselves to the first and sixth carbon in this lineup, replacing a hydrogen at each end. Picture it almost like two bookends of chlorine with a straight carbon chain between.
The structural formula helps connect the dots: Cl–CH2–CH2–CH2–CH2–CH2–Cl. You get this classic unbranched alkane format, with each end capped by a chlorine atom. This structure directs a lot of its chemistry, especially in reactions like nucleophilic substitutions. Life in the university organic chemistry lab sometimes means smelling that distinct sweet odor and using it to join things together in bigger molecules, especially where a six-atom spacer is needed.
Why It Matters in Chemistry and Beyond
In the real world, these details aren’t just trivia. They shape how 1,6-dichlorohexane acts and how researchers apply it. A compound with this structure finds a place as a building block for polymers, especially nylon variants, and specialized plastics. Its two reactive sites make it almost like a chemical double-ended wrench for scientists connecting molecules. When both ends are reactive, it opens doors in creating cross-linked materials or customizing surfaces.
Choosing 1,6-dichlorohexane in manufacturing brings precision. Its six-carbon chain lets chemists control the spacing between groups, and that impacts flexibility, melting point, and strength in the resulting polymer. Importantly, that span of six carbons isn’t random. Shift it to five or seven and physical qualities, including resistance to chemicals and durability, will change. A few years back, I spent nights in the university polymer lab, mixing and matching these chain lengths, watching material qualities shift under my fingertips and microscope.
Health and Environmental Concerns
Regular use means handling risks. Chlorinated hydrocarbons in general draw attention for possible toxicity. Direct contact brings skin and eye irritation, and breathing in fumes for longer can nudge the nervous system. Waste from these chemicals doesn’t play nice with nature—degradation takes time, and improper disposal lets them stick around in soil and water.
Working with these compounds, my lab group learned to lean into safety routines: fume hoods, gloves, chemical goggles, and careful record-keeping on waste. Regulations keep a close watch on chlorinated chemicals for workplace exposure and environmental release. The real trick is preventing leaks and spills, making certain every container gets the correct label, and double-checking every step in disposal.
Looking Forward: Sustainable Solutions
Safer alternatives and greener processes beckon, but replacing reliable tools like 1,6-dichlorohexane takes solid evidence. Research now points to using catalytic systems and finding ways to recycle or detoxify waste streams. Training pays off, too—many accidents come from missed steps or taking shortcuts. Pushing for better engineering controls and stricter monitoring of emissions will make a big dent over time. From molecule to end-use, this compound underscores the ongoing dance between utility and responsibility in modern chemistry.
What 1,6-Dichlorohexane Demands from Storage
1,6-Dichlorohexane may sound like a chemical tucked away in textbooks, but it rounds up in labs, industrial settings, and even university storerooms. I remember handling it during a project as a grad student. Nobody wanted a repeat of the spill from the last semester. We knew firsthand what mishandling could do—bad air, headaches, a search for the nearest eyewash station. If the chemical leaks, everyone in the room feels the sharp, chlorinated smell and irritation almost at once. Its volatility and reactivity mean storing it is never an afterthought.
Environmental Controls Matter
Placing 1,6-Dichlorohexane on any old shelf can brew trouble. The liquid evaporates quickly in warm spaces and throws off toxic fumes. I learned to stack it only in cool, shaded storage. The right temperature keeps the vapor in check. Standard practice calls for 2-8°C storage, often in a flammable materials fridge. Direct sunlight encourages degradation and leak risk. Life doesn’t pause, so mechanical cooling offers peace of mind even if the building’s AC cuts out. If the chemical sits unprotected from summer heat, the label might as well carry a warning: ‘To be inhaled by mistake.’ A stable indoor climate keeps staff safe and the environment unthreatened.
Material Compatibility Isn’t an Option
Some people place chemicals in any spare bottle or cabinet. With something as reactive as 1,6-Dichlorohexane, I never took that gamble. Polyethylene and glass containers block unwanted reactions. Steel, on the other hand, can corrode or spark a problem with this type of chemical. Seals need to fit tight—no cracks or aged caps. The cost feels minor compared to the medical bills or clean-up from a leak. I’ve watched labs cut corners, but in the end, they spent more replacing destroyed floor tiles and repainting stained storage rooms.
Isolation Prevents Bigger Problems
Mixing 1,6-Dichlorohexane with acids or oxidizers equals rolling the dice. This stuff reacts—sometimes violently. It belongs in dedicated cabinets marked “Hazardous Chemicals.” Flammable storage cabinets, rated and checked, give an extra layer of safety if a fire breaks out. Nearby shelves kept oxidizers and acids in my lab, but always on opposite ends of the storeroom. One shelf of carelessness means loss of chemical inventory or worse—an emergency room visit. Clear signage lets others know to leave well enough alone if they’re not trained for handling it.
Responsible Management: Beyond the Rules
I’ve found that even with perfect storage, trouble starts when policies live only on paper. Regular self-inspections catch degrading containers and missing labels. Training keeps everyone sharp—nobody gains from guessing or using outdated safety sheets. If I saw something wrong, I reported it and made sure it got fixed before heading home. At the end of the day, proper storage is about respecting both the law and chemistry’s stubborn facts. Simple steps like using the right fridge, locking up at night, and labeling containers save time, money, and possibly lives. The best storeroom isn’t just organized; it tells a story of care and respect for both people and chemistry’s demands.
Looking Closer at the Chemicals Around Us
Living in the modern age comes with an alphabet soup of chemicals in consumer products, plastics, and the air at our jobs. Every so often, a name crops up that prompts a closer look. 1,6-Dichlorohexane is one of those. This chemical finds its way into specialty polymers, coatings, and sometimes even batteries. Its uses may sound distant from daily life, but the risks it brings actually hit close to home in manufacturing towns and industrial spaces.
Not All Chlorinated Chemicals Are Created Equal
I’ve read enough safety data sheets and seen what happens in small factories to respect that term "chlorinated". The presence of chlorine atoms often means a chemical brings a set of hazards. According to the U.S. National Library of Medicine’s PubChem database, 1,6-Dichlorohexane may irritate skin, eyes, and airways. Even brief contact brings discomfort, while high exposures in labs can bring on headaches, dizziness, or even more serious neurotoxic effects. Animal studies show a risk of organ damage with heavy dosing. Few want to play lab rat with these risks.
Reports out of Chinese and European plastics producers often mention that escaping vapors from this chemical linger in the air. Volatile chemicals don't care whether you work on the line or manage the site from an office. Workers without proper gear—the ones actually touching these substances—take most of the hits. Chronic exposure draws concern for long-term impacts, such as cancers or reproductive harm. Chlorinated hydrocarbons tend to stick around in the body, sometimes showing ill effects years after exposure. That’s not just theory from a book; personal ties to chemical workers remind me of real folks who struggle with health problems after years around substances like this.
Thinking About the Environment
1,6-Dichlorohexane doesn’t just stay put. In the environment, it runs off factory floors or spills into drains, winding up in water and soil. Chlorinated solvents often break down slowly outside of laboratory conditions. Sunlight and microbes help, but not fast enough for busy waterways or community fields.
Wildlife in contaminated zones can suffer. Chlorinated hydrocarbons frequently crop up in studies of fish and amphibian health problems. Accumulation up the food chain isn’t rare either. When hazardous molecules turn up in well water, families start to worry. Real examples from past pollution cases—think Love Canal or more recent events with chlorinated solvents—show that clean-ups take years and cost millions. Living downstream or downwind means living with uncertainty.
Solutions That Put People First
Simple fixes rarely exist for chemicals in wide industrial use. Substitution counts as the gold standard. If manufacturers can swap out 1,6-Dichlorohexane for something less hazardous, lives improve. Green chemistry programs in Europe and North America actively scout for safer options, nudging the market in the right direction. On top of that, consistent ventilation, local exhaust, and strict personal protection for workers cut daily risk. Regulators sometimes lag behind, so pressure from workers and local communities gets results. Sharing air-monitoring data and spill reports should not feel like pulling teeth.
In my own experience watching chemical safety programs in action, real change happens where managers and floor staff pull together. Good practice becomes routine, not just response after someone gets hurt. Keeping up the push for health and transparency about where chemicals end up keeps risk from turning into tragedy. Raising a family near a plant, you learn to ask questions, look for data, and demand better controls. That’s not paranoia—it’s common sense built on hard lessons.
| Names | |
| Preferred IUPAC name | 1,6-dichlorohexane |
| Other names |
1,6-Dichlorohexane
Hexamethylene dichloride Hexane, 1,6-dichloro- NSC 11192 |
| Pronunciation | /ˈwʌn.sɪks-daɪˌklɔː.rəʊˈhɛk.seɪn/ |
| Identifiers | |
| CAS Number | 2162-98-3 |
| 3D model (JSmol) | `CCCC(CCCl)Cl` |
| Beilstein Reference | 900873 |
| ChEBI | CHEBI:16250 |
| ChEMBL | CHEBI:75313 |
| ChemSpider | 14218 |
| DrugBank | DB07962 |
| ECHA InfoCard | ECHA InfoCard: 100.022.216 |
| EC Number | 202-486-1 |
| Gmelin Reference | 82353 |
| KEGG | C01741 |
| MeSH | D003990 |
| PubChem CID | 12316 |
| RTECS number | MO3850000 |
| UNII | G046660A1R |
| UN number | UN3278 |
| Properties | |
| Chemical formula | C6H12Cl2 |
| Molar mass | 187.07 g/mol |
| Appearance | Colorless liquid |
| Odor | Odorless |
| Density | 1.08 g/mL at 25 °C |
| Solubility in water | Insoluble |
| log P | 2.85 |
| Vapor pressure | 0.13 mmHg (25°C) |
| Acidity (pKa) | 14.0 |
| Magnetic susceptibility (χ) | -7.74×10⁻⁶ cm³/mol |
| Refractive index (nD) | 1.461 |
| Viscosity | 2.215 mPa·s (25 °C) |
| Dipole moment | 2.11 D |
| Thermochemistry | |
| Std molar entropy (S⦵298) | 321.2 J·mol⁻¹·K⁻¹ |
| Std enthalpy of formation (ΔfH⦵298) | -204.7 kJ/mol |
| Std enthalpy of combustion (ΔcH⦵298) | -3507.7 kJ/mol |
| Hazards | |
| Main hazards | Harmful if swallowed, causes skin irritation, causes serious eye irritation. |
| GHS labelling | GHS02, GHS07 |
| Pictograms | GHS07 |
| Signal word | Warning |
| Hazard statements | H302 + H312 + H332: Harmful if swallowed, in contact with skin or if inhaled. |
| Precautionary statements | P210, P280, P305+P351+P338, P337+P313 |
| NFPA 704 (fire diamond) | 1-2-0 |
| Flash point | > 93 °C |
| Autoignition temperature | 285 °C |
| Explosive limits | 4.6–11.8% |
| Lethal dose or concentration | LD50 oral rat 1620 mg/kg |
| LD50 (median dose) | LD50 Oral Rat 1620 mg/kg |
| NIOSH | PY8060000 |
| PEL (Permissible) | Not established |
| REL (Recommended) | REL (Recommended Exposure Limit) for 1,6-Dichlorohexane: "1 ppm (6 mg/m3) as a time-weighted average (TWA) |
| IDLH (Immediate danger) | Unknown |
| Related compounds | |
| Related compounds |
Hexamethylene dichloride
Hexamethylene chloride 1,6-Dibromohexane 1,6-Diiodohexane 1,6-Difluorohexane 1,6-Dibromo-2,2,3,3-tetrafluorohexane |
