Chemistry always holds a few underappreciated gems, and 2-Acetyl-5-hydrothiophene falls into that camp. Back in the mid-1900s, researchers were getting curious about how sulfur heterocycles behaved, especially in industrial flavorings and fragrances. Demand came from both the rapidly expanding food industry and a new wave of synthetic organic chemistry. In my college lab days, I remember textbooks citing the unique odor notes of thiophene compounds. The research momentum built up as agrochemical and pharmaceutical companies hunted for new tricks in their molecular toolboxes. Sulfur chemistry suddenly offered more than just stink; it opened doors to more creative syntheses.
On the commercial scene, 2-Acetyl-5-hydrothiophene carries the CAS number 13329-46-9. It stands out as a yellowish liquid with a distinct, sometimes harsh aroma, reminiscent of roasted and nutty notes. Industries reach for it in creating savory flavors, fragrance compositions, and as a synthetic intermediate. I’ve worked with it on a benchtop scale, and its robust, almost meaty scent turns heads in a shared lab. Its wide use comes from this unique sensory punch matched with solid chemical reactivity.
The compound presents as a liquid at room temperature. Its molecular formula, C6H6OS, tucks in a five-membered thiophene ring decorated with an acetyl group at the 2-position. Boiling happens around 98-99°C at 13 mmHg, and it shows low solubility in water but good mixing with organics like ether or alcohol. On a practical level, it gives handling flexibility without becoming a runaway hazard under normal lab conditions. The smell, a mixture of toasted bread and sulfur, quickly lets you know a bottle’s open, so grip that cap tight and plan for proper ventilation.
Quality specifications for 2-acetyl-5-hydrothiophene have tightened over the decades, thanks to shifts in both regulations and user demands. A reputable supplier indicates purity above 98%, traces of solvent residue below 0.5%, and a density floating near 1.17 g/cm³ at 20°C. Labels now often include GHS symbols for irritancy or flammability, lot numbers for traceability, and batch-specific certificates of analysis. On receiving a drum, the checklist always includes a sniff test, a flashpoint reading (typically near 94°C), and a glance at the SDS binder.
The preparation centers around the Friedel-Crafts acylation route. Usually, the thiophene reacts with acetic anhydride in the presence of aluminum chloride. Getting a high yield means playing with temperature and reagent ratios, something every chemist tweaks depending on the scale. From my own pilot runs, cleanup involves distillation—oddly satisfying to see the colored product separate and collect in that receiving flask. Precursors remain cheap and common, which keeps prices reasonable as long as waste is managed properly.
2-Acetyl-5-hydrothiophene behaves like a classic aromatic, but the sulfur adds quirks. Electrophilic substitutions land mostly on the available positions of the ring, with further acylation or halogenation easy to achieve. I once used it to build up more complex pharmaceuticals, where the acetyl group acted as both a handle and later a target for reduction or condensation. Modifications don’t always stop at the ring: the acetyl group serves as a launching point for oximes, hydrazones, and even for linking to larger aromatic systems.
Trade and academic literature refer to this molecule under a spread of names. Common synonyms include 2-Acetyl-5-thiophene, 1-(5-thienyl)ethanone, and Ethyl 2-acetyl-5-thienyl ketone. Keep an eye on supplier codes too—sometimes a catalog will slip in “Thiophene, 2-acetyl-5-”. The naming confusion led me to double- and triple-check certificates before committing to a large purchase.
Handling practice lines up with most organic solvents. Splash goggles, nitrile gloves, and lab coats act as your first line of defense. Like many sulfur-containing organics, it carries the risk of eye and skin irritation, so fume hoods end up as more than just a formality. Flammable liquid labeling means no open flames or distractions during transfers. Even after careful work, containers need tight sealing and storage away from sunlight and strong oxidizers. From my own experience, a misplaced bottle means the sharp aroma lingers for days, so clean up spills fast and keep a full spill kit within reach.
2-Acetyl-5-hydrothiophene appears in an impressive lineup of industries. Food science uses it for formulating roast, grilled, or nutty top notes, with trace additions making a huge difference in flavor authenticity. Perfume chemistry counts on the molecule to mimic the “browned” facets in gourmand and oriental fragrances. Forty years back, the chemical gained favor in the synthesis of antihyperglycemic agents or antibiotics, opening up more applications in medicinal chemistry. Some of the more niche electronics fields use thiophene derivatives as conductive material precursors, especially in organic semiconductors and OLED technology. I’ve watched firsthand how a single compound pulls value from taste labs to high-tech cleanrooms.
Academic and corporate researchers keep exploring the boundaries here. Structural modifications unlock new flavor profiles and drug candidates. Universities dig into the underlying reactivity of the sulfur atom, while industry labs map synthetic routes to cut waste and processing time. My recent reading turned up exploratory work into new green chemistry approaches, like microwave-assisted syntheses or recyclable catalysts. The demand for high-purity thiophene intermediates pushes companies to invest in better process controls and purity assurance.
Toxicological work shows that, like most volatile organics, 2-acetyl-5-hydrothiophene poses health risks at elevated exposures. Rats exposed to high vapor levels show mild central nervous system effects. Based on the sulfur content, inhalation produces irritation; chronic contact events led to skin sensitization in test species. Regulatory reviews for food and fragrance applications set strict thresholds, mandating microgram quantities in finished products. Labs I’ve worked in require airtight logs for handling and separate waste streams to limit both personal and environmental exposure.
Chemical innovation rarely stands still, and 2-acetyl-5-hydrothiophene looks set for a broader role. Food safety rules drive research into more sustainable, less toxic derivatives. In electronics, demand for organic materials could soon call for higher-grade thiophene intermediates. Pharmaceutical companies continue to screen its skeleton for new activity, keeping researchers busy. From my perspective—split between process development and benchwork—chemicals combining unique odor, reactivity, and easy handling will carve bigger spaces in future industry and research pipelines.
Step into any lab where flavors and fragrances are developed, and you’re likely to hear about 2-Acetyl-5-Hydrothiophene. This name sounds like a mouthful, but at its core, this molecule isn't a unicorn—just a clever bit of sulfur chemistry tied together with a pinch of carbon.
Look at this molecule’s formula: C6H6OS. That’s six carbons, six hydrogens, a single oxygen, and one sulfur atom. Picture a thiophene ring—five atoms making up a circle, four carbons and one sulfur. Attach an acetyl group (that’s a COCH3) to the second carbon, counting from that sulfur atom, and you’ve mapped it out. At the fifth position of the ring, you get a hydrogen, so nothing extra to tack on there.
Most people haven’t held a model of thiophene in their hand, but try to imagine a flat, five-sided ring where one corner is sulfur. It’s like the difference between regular bread and rye—sulfur really shifts the taste, and in chemistry, it shapes reactivity and scent. The acetyl group sticks out from the second carbon and changes everything. Chemists scribble the molecule as: OC(C2H3)-Thiophene with the major functional group (acetyl) drawing attention at position two.
Here’s the chemical structure, for those who work with atom-to-atom connections:
The fact that one functional group, like acetyl, can reshape a molecule’s behavior stands out. For those in food science, this isn’t just trivia. Many savory snack flavors rely on minute quantities of 2-Acetyl-5-Hydrothiophene for that roasted, oniony edge. Even tiny changes—moving the group to another position—mean the molecule smells and reacts differently. A little chemistry class anecdote: I once tried to mimic the scent of French onion soup for a project, and the literature pointed to this exact compound as a game-changer, producing the right balance between savory and sweet sulfur aromas.
Structure speaks the language of function. Sulfur rings alone can swing from pleasant to rank. Drop the acetyl group at the right spot, and suddenly the compound plays nice—warm, inviting, a favorite among flavorists. That’s why knowing the structural fingerprint matters, especially if you’re working with consumer goods where a sniff or a taste feeds straight into the bottom line.
Misunderstanding a molecular structure can be costly. Use the wrong isomer, and the flavor could tank a whole batch of product. Also, sulfur chemistry sometimes brings irritants, which adds complexity for safety teams in manufacturing. Clear records, solid quality control, and a habit of always double-checking chemical shipments—these steps avoid headaches. Partnering with trustworthy vendors and using analytic tools like NMR or GC-MS keeps things on target.
Flavor creation isn’t the only arena for 2-Acetyl-5-Hydrothiophene. This compound gets nods in pharmaceuticals, where sulfurated rings crop up in drug development. Its role as a synthetic intermediate highlights why structural understanding bridges the worlds of sensory experience and technical invention.
One small change on a molecular scaffold transforms everything, and 2-Acetyl-5-Hydrothiophene stands as proof. Crack open the chemical structure and formula, and possibilities unfold—from a tastier potato chip to a safer, more creative chemistry lab.
Plenty of people never think twice about what gives a croissant or fresh bread its signature aroma. That everyday mouthwatering smell doesn’t always come from an actual bakery. Sometimes it shows up because of compounds found in food flavoring labs. 2-Acetyl-5-Hydrothiophene is one of the unsung heroes there, tossed into the mix to recreate the roasted, bready, and occasionally cheesy notes that make snacks and treats so tempting.
Food scientists are always searching for ways to boost flavor in packaged foods. I’ve seen this chemical listed in the flavor formulas for snacks, dairy-based desserts, and even meat analogs designed for plant-based diets. The reason is straightforward. Not every company can bake fresh bread on-site, but everyone wants their product to spark that craving on the first sniff.
What feels clever is how fragrance houses have latched onto 2-Acetyl-5-Hydrothiophene. Beyond food, perfumes and room sprays borrow this molecule when crafting those fresh-from-the-oven vibes or subtle musk notes. There’s no magic in it — just careful balancing. The same compound that says “fresh bread” also brings warmth to fine fragrances and candles. Sometimes, perfumers even blend it with vanilla or coffee-like aroma molecules to chase something comforting, almost nostalgic.
Learning about how synthetic notes combine with natural ones opened my eyes to how much chemistry lies behind everyday pleasures, like coming home to a house scented like something just baked. One drop from the lab beats hours baking from scratch, at least in terms of pure scent payoff.
Some folks forget that chemicals serving the perfume bottle or snack aisle can play big roles in industrial settings. 2-Acetyl-5-Hydrothiophene steps into pharma labs as a versatile building block. Since its molecular structure offers both a thiophene ring and an acetyl group, it creates a launchpad for making more complex drugs and fine chemicals.
If you look at patents from the last decade, you’ll spot this molecule cropping up as a raw material in work on antibiotics, pesticides, and specialty polymers. Its electron-rich structure means that medicinal chemists can transform it in a bunch of directions, chasing new activities or boosting solubility. In my own reading, chemists talk about this intermediate as a “workhorse” for new heterocyclic compounds, handy because it’s robust, doesn’t break the bank, and joins up with many different chemical partners.
Every chemical shortcut raises questions. Anyone working with flavor chemicals must think hard about regulatory hurdles, clean labeling, and possible allergy or safety concerns. 2-Acetyl-5-Hydrothiophene gets flagged for scrutiny since food and perfume use affects a lot of people. The scientific community often teams up with regulators to set limits and review long-term data. Big brands tend to play it safe — relying on less controversial chemicals when possible or listing trace amounts honestly.
As much as I love the science behind flavor molecules, better dialogue between food chemists, regulators, and consumers would help build more trust. If companies invested in transparent sourcing and clear, jargon-free ingredient lists, folks shopping for food or perfumes would get some confidence that those aromas aren’t just dreamy but safe as well.
Most folks see chemical names like 2-Acetyl-5-Hydrothiophene and picture endless pages of safety data and obscure jargon. A conversation about its storage starts and ends with “keep it in a cool, ventilated space.” But let’s dig a layer deeper. Drawing from twenty years poking around university labs and batch production floors, I’ve learned that a little slip-up turns any exotic compound into a real challenge—and 2-Acetyl-5-Hydrothiophene, with its sulfur tang and flammable volatility, fits the bill.
Leave this stuff on a crowded bench, and the sharp, oniony smell escapes even when capped tightly. That’s not just unpleasant—it ruins air quality and signals a vapor risk. Sulfur-based chemicals never play nice with oxygen or sunlight for long. Instead, stash this compound in a tightly sealed glass bottle. Forget those leaky plastic containers lining high school storerooms; they get soft, and volatile organics chew through them over time.
Where that bottle sits matters most. Stash it in a cool place, far from direct sunlight. Heat speeds up volatility. Let this chemical climb much above room temperature and vapor pressure jumps, nudging the risk of a pressure build-up or nasty leak. I once watched a neglected bottle distort its cap by midsummer, leaving a whole room reeking like burnt coffee and rubber.
Airflow saves headaches and noses. Whether it’s a closet-sized chemical store or some dusty shelf upriver from the lab benches, you want good, steady ventilation. I’ve seen closets crammed with bottles that, on a warm day, fill with hot fumes—an accident waiting to happen. It isn’t paranoia when fume risk pushes you to install that extra extractor fan or choose lower shelves where heat collects less.
Gloves, goggles, and lab coats—these aren’t fashion accessories. If you handle this compound, even for weighing or bottling, double-check your gloves are nitrile or something stronger; latex folds fast under organics. Clearing spills fast matters, too. Sulfur odor lingers forever. After one batch process, the whole lab reeked for a week because someone wiped a spill with a dry rag instead of using an absorbent pad and solvent rinse. Don’t shortcut cleanup—sulfur-based volatiles hang around.
Inventory matters for more than accounting. Local fire codes take a dim view of stockpiles of flammable organics, especially among sulfur-based compounds. Keep purchase records and shelf-life data close. Rarely used bottles expire, react with moisture, and turn unpredictable. Cycle through inventory every six months. If something smells off, looks cloudy, or the cap shows crust—dispose of it following hazardous waste guidelines. Incineration or certified hazmat disposal is safer than “just pouring it down the sink,” which I saw nearly happen at a university once until someone intervened.
Not every risk disappears with a checklist. Improved storage standards matter most where folks do the grunt work—chemical stores, small research outfits, teaching labs. Real progress shows in quiet rooms and safe workers, not spotless paperwork. Small habits—a tight cap, good ventilation, prompt disposal—keep even old labs livable. That lesson sticks more than any lecture—because you remember the day the smell clung to your shirt until you threw it out.
If you've ever worked around flavors or fragrances, you might have brushed shoulders with 2-Acetyl-5-Hydrothiophene. This compound brings in that roasted, nutty aroma often found in foods. On paper, it looks like just another flavor agent. On the job, it commands respect.
Most people in production facilities or research labs spot chemicals like these every day. Over time, you develop a sixth sense for the odd smell or a sticky residue. 2-Acetyl-5-Hydrothiophene carries a distinct sulfur note—you won’t mistake it. That scent signals more than flavor: it hints at volatility and reactivity.
Things can go sideways if you ignore personal protection. Inhaling vapors from this compound irritates airways. In high concentrations or poorly ventilated places, headaches set in quick, followed by nausea. Eyes and skin feel the sting with direct contact. You wipe your face with a gloved hand and, suddenly, you’re running for eyewash. That lesson sticks after the first accident.
Flashpoint looms over anyone handling 2-Acetyl-5-Hydrothiophene: it can ignite at just 78°C. All it takes is a small spark. Years ago in a flavor house, a loose electrical cable in a mixing area sent a spark through the air, lighting up a spill that hadn’t even dried yet. Nobody got hurt, but it’s a story everyone brings up at safety training.
Many chemicals in this class build up flammable vapor. Good airflow and closed containers aren’t recommendations—they’re non-negotiable. If containers don’t get sealed immediately after use, the vapor drifts and, before long, small accidents turn big.
Reading labels isn’t enough. The people who stay safe gear up. Nitrile gloves, splash-resistant goggles, long sleeves. Good habits build up: work near a fume hood, never pipette by mouth, check every bottle for leaks before moving it. Spill kits sit within reach. It’s easy to overlook routine checks, but complacency is the real hazard here.
Past exposure stories highlight where safety can fall short. I’ve seen teams skip respirators for “just a quick sample.” The one time it mattered, someone coughed through the day, barely able to speak by evening. Safety goggles prevent the frantic scramble for a rinse station.
Rules matter, but culture trumps written policy every time. When supervisors demonstrate best practices—never cutting corners, always double-checking safety stations—the whole team watches and follows suit. This isn’t about nagging. It’s recognizing that one careless move with sulfur compounds costs everyone, not just the person holding the pipette.
Regulations from OSHA and similar agencies require proper labeling, accessible data sheets, and incident reporting. Having all that, plus an emergency plan you actually practice—not just once for the audit—keeps people prepared. If you work somewhere that treats every incident as a learning moment, you see real improvement over time.
Hazards tied to 2-Acetyl-5-Hydrothiophene don’t just fade with familiarity. The risks are real, from respiratory irritation to sudden ignition. Staying safe means a mix of the right gear, solid habits, open conversations, and a culture that takes every incident seriously. Earning that kind of workplace takes effort, but it beats the alternative—every time.
Dealing with specialty chemicals like 2-Acetyl-5-Hydrothiophene involves more than a keen interest in chemistry. Packaging matters just as much as purity, especially when storing volatile or odor-intensive compounds for any length of time. In real labs, I’ve found that suppliers ship this chemical in tightly sealed amber glass bottles for small batches, especially for analytical or research settings. If you’re working in a flavors or fragrance company that buys in bulk, don’t expect glass; you’ll face aluminum drums or steel containers, always air-tight and often nitrogen-flushed. Even a few milliliters escaping can disrupt a workspace and ruin delicate experiments.
Quality isn’t just a label. The purity specification for 2-Acetyl-5-Hydrothiophene shapes its performance in both analytical and production environments. Reputable producers always list a minimum purity of 98%, often pushing for 99%. This tight margin matters, since a single percent of impurity can shift a flavor profile or skew an instrument reading beyond recovery. Imagine spending days prepping a sample for GC-MS analysis only to realize a contaminant from a sloppy batch caused misleading peaks. Fixing that wastes everyone’s time.
Not all impurities are equal, though. Water content, for example, can creep up fast if a container isn’t sealed right, especially in humid regions or in older warehouses. A sharp nose can usually detect when a drum has gone bad, but most labs rely on gas chromatography or HPLC to verify purity before use. Experienced technicians trust their instruments, but the occasional sniff test remains a reality check in smaller setups. Quality also depends on how the supplier stores and handles each batch. I’ve seen some who skip vital steps just to cut costs, which always comes back to bite them — and their customers — later on.
Chemicals like 2-Acetyl-5-Hydrothiophene aren’t friendly to sunlight or moisture. Standard instruction is to keep them in cool, dry places, away from light and heat. Even so, corners get cut more often than folks like to admit. Leaky seals, reused drums, or mixed-up labels invite headaches ranging from mild contamination to full product recalls. These failures waste money and erode trust.
Packaging choices often drive waste, too. I’ve opened drums that held a quarter-inch of residue, simply because the container was too wide for the siphon used during transfer. Small glass bottles minimize loss but only fit niche labs or low-volume processes. Industrial buyers have to wrangle with scale, cost, and safe disposal of empty tins — rarely a seamless process. Shipping regulations add hurdles, especially for international moves, where customs checks go beyond paperwork and may expose packages to delays that degrade sensitive contents.
I’ve seen great results from sticking with suppliers who prioritize both product integrity and user safety. Look for transparent documentation, clear batch numbers, and certificates of analysis with every order. In-house verification tools like portable GC units can catch problems early, but proper training makes or breaks these safeguards. Advocating for vendor accountability, especially in regions with weaker enforcement, drives up quality across the supply chain. If you’re stuck with inconsistent batches or sketchy handling, it’s worth paying for better service elsewhere — long-term savings often follow.
Recycling drums and glassware brings another challenge. Industrial sites should push suppliers to accept returns or offer safe disposal services, cutting down on environmental harm from leftover chemicals. As more businesses ask about this, I’ve noticed the market shift toward closed-loop solutions, which keeps both the lab and the planet cleaner in the long run.
