The early interest in pyrrole derivatives emerged during the growth of the synthetic organic chemistry field, as researchers looked for new heterocycles to build complex molecules and pharmaceuticals. 1-(O-Chlorobenzyl)-1H-Pyrrole, stemming from classic pyrrole chemistry, grabbed attention when halogenated benzyl groups triggered new biological activity in lead optimization studies, especially through the 1970s and 1980s. These pursuits focused on selective substitution on both aromatic and heterocyclic rings, aiming for unique reactivity or pharmacological action. I’ve come across references to its synthesis in archived medicinal chemistry journals, where it appeared in small molecule libraries designed for antimicrobial screening. The journey from lab curiosity to a recognizable scaffold in fine chemical and pharma catalogues speaks to how nuanced tweaks in molecular structure often drive scientific progress.
1-(O-Chlorobenzyl)-1H-Pyrrole brings together a pyrrole ring—well known in biomolecules and drugs—with a benzyl group, para-chlorinated for added properties. Chemists and product developers often turn to it as a versatile intermediate, making it valuable for libraries in agrochemical lead discovery, material science studies, and sometimes as a reference compound in environmental analysis. Across suppliers, the product gets defined not just by purity, but also by documentation detailing toxicity, storage, and compatibility with particular solvents or reagents. Production scale and regional regulatory status can affect sourcing and handling. To my knowledge, companies in the US, Europe, and parts of Asia have commercialized small-gram quantities for lab use, with purity commonly tested above 97%.
As a compound, 1-(O-Chlorobenzyl)-1H-Pyrrole holds onto the volatility and low aqueous solubility typical of many substituted pyrroles. The presence of the chloro group labels it as lipophilic, making it more likely to dissolve in nonpolar organic solvents like dichloromethane or chloroform. A pale yellow to light brown oily liquid or low-melting solid, its aromatic rings give a modest resonance stabilization, which shows up in moderate UV absorbance and NMR spectra that feature signature chemical shifts for pyrrolic protons and the ortho-chlorinated phenyl ring. Molecular weight falls in the range of 217-220 g/mol, and the density approaches that of water but typically stays a bit lighter—these features affect how it layers out in separation workups or when portioning out in glass syringes or pipettes.
Standard technical specs address purity, water content, and the absence of residual starting materials or key impurities above 0.5%. Analytical certificates from trusted suppliers usually provide melting points, GC-MS or HPLC chromatograms, and sometimes IR spectra. Product labels carry the CAS number, batch ID, hazard pictograms relevant for organochlorine compounds, and recommendations for keeping the material sealed, dry, and away from sunlight. A safety data sheet accompanies orders, spelling out chemical and physical hazards, storage temperature recommendations (often at 2–8°C), and personal protective equipment—lab coats, gloves, goggles—needed during routine handling.
Synthesis often leans on nucleophilic substitution: starting with O-chlorobenzyl chloride, a common protected benzyl halide, and reacting it with pyrrole under basic conditions. Sodium hydride or potassium carbonate, stirred in polar aprotic solvents like DMF or DMSO, enables the alkylation of pyrrole nitrogen. The reaction temperature stays moderate—usually around 20°C to 30°C—to limit side products. After workup, column chromatography with a petroleum ether/ethyl acetate mix helps isolate the target molecule. The yield usually hits 60–85%, depending on scale and the thoroughness of exclusion of water and air from the system. In academic labs, students get hands-on experience here while learning about alkylation strategies and troubleshooting purification stages.
The pyrrole moiety in 1-(O-Chlorobenzyl)-1H-Pyrrole supports further electrophilic substitution, especially at the 2 and 5 positions of the ring. Halogenation, acylation, or formylation steps find a foothold if more complexity or binding site diversity is needed. The benzyl chloride group can get replaced in multi-step syntheses, serving as a handle for Suzuki, Heck, or other cross-coupling strategies when building fused aromatic systems. In exploring reactivity, researchers often map electronic influences from the ortho-chloro group, finding shifts in nucleophilicity and changes in the product mix versus non-chlorinated versions. Insights here have a spillover effect into both synthetic theory and industrial application.
Within catalogues and scientific papers, you’ll see 1-(2-chlorobenzyl)pyrrole, o-chlorobenzylpyrrole, or N-(2-chlorobenzyl)pyrrole used interchangeably. Regulatory filings sometimes add the systematic IUPAC name or longer forms mentioning the pyrrole 1-position as the site of substitution. Awareness of these synonyms cuts confusion in procurement and literature searching, helping avoid mix-ups with para- or meta-chlorinated analogues or compounds bearing the chloro group on the pyrrole ring instead.
Organohalogen compounds carry certain risks that chemists cannot ignore. With 1-(O-Chlorobenzyl)-1H-Pyrrole, moderate acute toxicity, skin and eye irritation, and environmental hazards enter play, especially when spills occur or during large-scale handling. Labs keep materials stored in tightly closed amber vials inside ventilated enclosures, away from strong acids or oxidizers, and label waste for halogenated organics disposal. Personal experience tells me that well-written standard operating procedures, annual safety training, and up-to-date chemical inventories make these risks manageable on a day-to-day level. Engineering controls, such as fume hoods and chemical-resistant surfaces, back up effective PPE use, and spill kits for organochlorines remain handy near synthesis benches.
Investigators and industrial chemists draw on 1-(O-Chlorobenzyl)-1H-Pyrrole’s capabilities in pharma discovery, where small structural shifts can generate new lead compounds with antibacterial, antifungal, or CNS-modulating effects. Agroscience departments occasionally include it in pesticidal screening, thanks to the electron-withdrawing nature of the chlorine providing unique binding to biological receptors. The electronics industry sometimes highlights pyrrole derivatives in the search for novel conductive or semiconducting polymers, although o-chlorobenzyl substitution’s real niche lives in specialty reagents, analytical standards, and intermediate stages in multi-step synthesis. Researchers flag it as a building block for custom heterocyclic synthesis, especially where halogenated aromatics play a role in mimicking natural product motifs.
Contemporary R&D explores not just new reaction methods—like microwave- or flow-assisted synthesis—but also greener solvents or catalytic routes for attaching the chlorobenzyl group to the pyrrole core. Teams screen derivatives for biological activity, measuring inhibition rates against microbes, enzymes, or cancer cells, and sometimes feed results back into iterative design cycles for patenting new molecules. Having worked on related scaffolds in graduate school, I know the pain points: balancing synthetic accessibility, reproducibility, and economic cost while chasing new functionality remains a tough equation. Companies hope for breakthroughs either in new applications—like supramolecular chemistry or responsive materials—or in process safety that shrinks solvent and energy footprints.
Studies on toxicity paint a cautionary picture: organohalogens in this class sometimes disrupt aquatic life at low concentrations and show moderate cytotoxicity in mammalian cells. Exposure data stay limited, but animal studies in journals suggest handling with care, consistent with its SDS hazard pictograms. Lifecycle analysis points out the environmental persistence of aromatic chlorinated compounds as a long-term concern for water and soil. Occupational health reports stress the importance of containing vapors, keeping good air exchange in labs, and monitoring waste streams so they do not impact municipal water supplies.
As chemists push for more sustainable, selective, and safer synthetic routes, 1-(O-Chlorobenzyl)-1H-Pyrrole stands not just as a product of legacy chemistry, but as a candidate for redesign. Moving forward, collaborative research could yield better catalytic systems for its creation, lower-burden alternatives non-reliant on hazardous chlorinated solvents, and real-time analytics to predict toxicity or degradability before scale-up. Regulatory tightening in regions with strict organohalogen emission controls could reshape its availability and push the scientific community toward non-chlorinated analogues or more benign halogen sources. Industry trials, academic partnerships, and open-access data sharing look set to map out the next chapter in this compound’s story, with safety, performance, and sustainability driving decisions in the lab and the marketplace.
Curiosity around chemicals with complicated names isn’t just for lab workers — people working in agriculture, public health, and even environmental science have good reason to pay attention. 1-(O-Chlorobenzyl)-1H-pyrrole doesn't roll off the tongue, but this compound deserves a bit of spotlight, especially as the world keeps trying to balance productivity and safety.
Over the years, this molecule turned up as an ingredient in a class of chemicals known as fungicides. Companies put it to work fighting fungal diseases that threaten crops. The structure combines a pyrrole ring and a chlorinated benzyl group, which isn’t just chemistry trivia — this mix packs enough punch to disrupt the cycles of some stubborn plant pathogens. The agricultural sector looks for these qualities because plant fungal infections cost farmers billions each year. Resistant strains keep popping up. New answers are needed, and chemicals like this one help fill that gap.
Nothing goes unquestioned these days, and that's a good thing. Many people remember stories of another chlorinated chemical — DDT — and its long shadow over health and ecosystems. Scrutiny surrounds any new agent: researchers test toxicity levels, watch how the chemical breaks down in soil and water, and collect data on any drift into the food chain. The goal is to hit pests or pathogens hard without troubling pollinators, mammals, or humans.
If you talk to agricultural advisers or university researchers, you'll hear a mix of measured optimism and concern. In some cases, regulators limit usage or recommend mixing different management tools so resistance doesn’t build. Just like antibiotics in the clinic, relying too much on one solution can backfire. Crops like peanuts, wheat, or fruits often get most of the help, as fungal diseases see these fields as giant buffets.
Some of these chemicals cross over into other areas. Biocidal properties catch interest in public health and environmental cleaning. Hospitals, water treatment plants, and sometimes even pest control operators tinker with similar structures when fighting mold or mildew. But tighter regulations and growing demand for organic food keep changing the landscape.
Every answer in chemistry brings new puzzles. Alternatives based on biological control — using beneficial microbes or clever farming practices — show some promise. Integrated pest management tries to keep chemicals as just one backup tool in a bigger strategy, where monitoring, crop rotation, and healthy soil cut down the threat before it starts.
At the same time, precision spraying and chemical engineering bring hope that less might do more. Focusing only where and when a crop truly needs help can ease environmental impact. Research doesn’t stop, and new studies add to a growing body of knowledge on how exposure plays out across landscapes, animals, and us.
1-(O-Chlorobenzyl)-1H-pyrrole reminds people that the fight for healthy crops or cleaner environments keeps changing. Farmers, teachers, scientists, and families all play a role in demanding transparency and balance. Watching how new solutions work in practice — not just on paper — helps steer smart decisions, whether you’re growing a backyard tomato or running a bakery that relies on clean, safe wheat.
1-(O-Chlorobenzyl)-1H-pyrrole draws its character from both its parent structures: pyrrole and o-chlorobenzyl. The pyrrole ring—a five-membered aromatic ring with one nitrogen atom—often finds itself in the stories of both pharmaceuticals and organic semiconductors. Add the o-chlorobenzyl group, which means a benzene ring bearing a chlorine atom in the ortho position attached through a -CH2- linker, and you get a molecule with moods from both worlds.
Chemists write its molecular formula as C11H10ClN and often sketch its skeleton as:
This sort of connectivity offers more than a tidy diagram in textbooks. It shapes the way the molecule reacts, bonds with others, and finds its spot in different chemical applications—from drugs to dyes.
Every scientist knows that a tiny tweak—like shifting a chlorine atom from one position to another—can flip a molecule’s effects. The ortho-position on the benzene makes the chlorine’s influence reach further, both electronically and through the bulk it introduces. In my experience running reactions, that ortho-chlorine often brings steric hindrance, making it trickier to push through some substitutions. The location of that chlorine puts this derivative in a whole different basket than its para or meta cousins. It can even affect how the molecule fits into biological receptor pockets, changing its utility in drug research.
The one nitrogen in the pyrrole part can act as a site for hydrogen bonding, and it also changes how the molecule absorbs light—a reason pyrrole rings sneak into pigment chemistry. The benzyl group lumps on extra mass and tailors the electron density across the whole structure, tweaking its reactivity in ways visible only to those who have seen their reaction flasks change color at the drop of a base.
Trying to synthesize 1-(O-chlorobenzyl)-1H-pyrrole in the lab? Plan for some careful steps. That ortho-chlorine pushes you to play with solvents and base strength, to avoid side reactions or reduced yields. Getting a pure sample takes a little more work and patience. I remember needing extra rounds of chromatography, just because the ring system drags in more close relatives from byproducts than you’d expect.
Every molecule tells a story about safety, too. Chlorinated aromatics can pose risks—think waste handling and exposure limits. Working with such compounds means making real decisions about personal protection, waste practices, and even substitute planning if the chemistry gets too hairy. These aren’t abstract industry guidelines; I’ve seen colleagues develop rashes or headaches from skipping gloves or fume hood work. It pays to treat this chemistry with tangible respect.
Lab workers and industry professionals can use precise chemical structures to design safer reactions, select greener solvents, and choose more sustainable pathways. Methods that reduce chlorinated waste help the next generation avoid the mistakes of old. If a molecule’s structure points toward hazards, careful process design and automation can make the difference between routine work and a trip to the emergency room.
Getting comfortable with the fine points of structures like 1-(O-chlorobenzyl)-1H-pyrrole changes the conversation in both classrooms and factories. It reminds us that chemistry always demands both attention and adaptation, as research and industry keep pushing for safer and more effective outcomes.
Handling chemicals like 1-(O-Chlorobenzyl)-1H-Pyrrole demands serious attention. In my time working in academic research labs, I saw how poor storage choices could lead to contamination, waste, or even danger. With this compound, paying attention from the start saves headaches down the line.
Moderate, controlled temperature makes the difference. Pyrrole derivatives, especially those with halogen substituents like this one, tend to degrade faster in fluctuating or high heat. Storing at room temperature in a stable, dry, and shaded location often works best, but some suppliers recommend refrigeration to minimize impurity formation. Cold storage slows chemical reactions and keeps the material fresh. Letting the jar sit near radiators, windows, or warm equipment risks chemical breakdown—never worth it.
O-Chlorobenzyl derivatives show sensitivity to light and sometimes humidity. Amber glass containers block UV that can otherwise trigger unwanted changes. Tight seals with silicone or PTFE-lined caps prevent moisture in the air from creeping in—humidity can both promote hydrolysis and cause the compound to cake up or degrade. My own experience with leaky lids turned into hours spent cleaning up sticky, ruined product. So, picking the right container and securing those lids always comes first.
Strong-smelling or volatile compounds, including chlorinated aromatics, can give off fumes that add risk during storage. Chemical cabinets with good ventilation make a huge difference—not just for protecting staff from inhaling vapors, but also for cutting down the risk of reactions if containers crack open. Chemical inventory management systems remind us how many minor incidents come down to someone skipping ventilation, sometimes just out of impatience.
Mixing incompatible chemicals cause more drama than any other storage mistake. Chlorinated pyrroles react with strong oxidizers, acids, or alkali. Keeping these substances on dedicated shelves stops cross-contamination and reduces the odds of a dangerous reaction if something spills. Where I worked, labeling was obsessive—but that’s what kept everybody safe.
Recording every storage condition and lot number turns out useful when something goes off-spec. Keeping a log—date in, source, temperature, observations—helps track the life of the material and catches problems early. In regulated industries, inspectors not only want to see proper storage—they want proof that it’s been kept up, batch after batch. That log, tedious as it feels, has saved my teams more than once from last-minute surprises.
Sometimes, routine gets interrupted. Gloves, goggles, and lab coats don’t just protect against big spills; they shield skin from small leaks or dust you don’t see during everyday handling. Emergency eyewash and spill kits belong in arm’s reach nearby. The handful of times someone cut corners out of habit usually turned into hard lessons—taking a minute to gear up is always faster than treating a chemical burn.
Staying up to date with new safety data sheets, supplier guidelines, and university safety seminars contributes more than most realize. Organizations like the American Chemical Society and OSHA maintain updated recommendations. A chemist’s habits shape the careers and well-being of everyone in the lab.
Good storage practice for 1-(O-Chlorobenzyl)-1H-Pyrrole protects people, protects the product, and keeps costs under control. These small steps—attention to temperature, humidity, light, segregation, proper documentation, and safety gear—matter far more than most imagine.Chemicals with long, complicated names often make us uneasy, and 1-(O-Chlorobenzyl)-1H-pyrrole fits that mold. This molecule finds use in organic synthesis and sometimes as an intermediate in pharmaceuticals or agrochemicals. Its structure includes a chlorinated benzyl group attached to a pyrrole ring—two chemical features that can influence how it behaves in the body or environment.
Whenever I come across a new compound in the lab, my first move involves checking hazard databases and scientific literature. Reliable resources like PubChem and ECHA (European Chemicals Agency) currently list 1-(O-Chlorobenzyl)-1H-pyrrole with limited toxicological data. No widespread reports flag this specific compound as highly poisonous, yet related molecules in its family—chlorinated aromatics and substituted pyrroles—sometimes show toxicity, whether through skin contact, inhalation, or ingestion.
In practical terms, even if the official documents don’t scream “danger,” certain groups of chemicals earn reputation for being tricky. Chlorinated aromatic compounds, for instance, often turn up in discussions around persistent organic pollutants or skin irritants. Pyrroles carry another risk—sometimes they transform in the liver, generating reactive intermediates that harm tissue, or even act as precursors to substances with cancer risks. If I spilled this chemical in the lab, I wouldn’t treat it like sugar water. Proper gloves, goggles, and good ventilation would be my go-to precautions. Experience tells me that caution and prevention beat regret and accidents.
The next consideration involves what happens if this chemical escapes a controlled setting. Waterways and soil sometimes suffer lasting effects when chlorinated organics enter the picture. Because governments expect businesses to prove environmental safety, effluent monitoring and treatment become necessary steps. In manufacturing environments, chemical workers face more routine exposure than the public. Even without firm toxicity data, most safety officers require fume hoods, spill kits, and regular air monitoring around substances with structural similarities to known toxicants. Occupational exposure limits may not exist yet, but relying on basic industrial hygiene practices makes a real difference.
Given how little specific information exists about 1-(O-Chlorobenzyl)-1H-pyrrole, regulatory agencies would likely categorize it under the “handle with care” umbrella. The lack of data usually pushes companies to look at safety data sheets (SDS) for guidance, and these documents almost always advise personal protective equipment and minimizing dust or vapor generation.
Back in my university days, a professor repeated the same mantra about unknowns in the chemical world: Respect every bottle, test in small quantities, and keep emergency plans ready. His advice holds true for newer or less-researched compounds like this one. Building a culture where people feel free to flag safety questions, even for chemicals that seem obscure, sets the tone for healthier workplaces.
The best approach for any business that handles 1-(O-Chlorobenzyl)-1H-pyrrole involves adopting conservative safety rules, investing in employee training, and supporting transparent reporting of near-misses or accidental exposures. It also helps to push for more research—encouraging scientists and regulatory bodies to fill in the blanks so that confusion doesn't become complacency. Transparent communication of risks — not whispering in the break room — lowers the chances of harm.
In the end, trusting proper chemical management leads to both worker safety and environmental protection, even for substances that haven’t yet hit the headlines.
In chemical manufacturing, purity often separates the useful from the unreliable. 1-(O-Chlorobenzyl)-1H-pyrrole sits among those specialty building blocks favored in pharmaceutical labs and advanced material research. Reliable suppliers typically state purity as a percentage, with industry benchmarks usually demanding at least 98%. If purity falls any lower, confidence drops, especially for synthesis that leads directly to sensitive applications like active drug ingredients.
Lab technicians may see a certificate showing “98%” and feel satisfied. But actual value comes from knowing what that 2% impurity consists of. Chlorinated aromatics, for example, sometimes drag byproducts from incomplete reactions or trace solvents. These leftovers may wreck a reaction or force extra rounds of purification downstream—wasting money and time.
I recall working on a scale-up process with a vendor sample. Its spec sheet read “97% by HPLC” but ignored volatile residues. That subtle oversight landed us with a nasty chromatogram and delayed our project by weeks. Product specs that clearly define impurity profiles, loss on drying, and even heavy metals end up saving the most in long-term hassle.
Many buyers focus only on the headline purity value. They may not scrutinize what techniques were used. Purity measured by HPLC gives a more nuanced, trustworthy picture than melt-point or “area normalization.” Reputable producers share detailed chromatograms, not just raw numbers.
Key specs to watch:
At bench scale, stray impurities may seem easy to ignore. In pilot or full production, they threaten batch rejection, regulatory problems or unplanned waste disposal costs. More than once I’ve watched a promising reaction turn into a lesson in humility because of “mystery peaks” contaminating a raw material. That turns routine synthesis into detective work, costing more than tough questions and up-front diligence ever would.
Asking for full analytical data helps take guesswork out of the picture. Ordering small test lots before committing to a bulk shipment can identify vendor shortcuts. Long-term trust comes from suppliers who welcome questions about their process and don’t dodge requests for COAs or method specifics.
Also, in sectors where trace contamination may pose real health risk—think pharma, agrochemicals, medical-device coatings—regulatory scrutiny rises dramatically. Trying to pass off lower-purity technical material in these areas risks damaging reputations and even facing legal trouble.
Demanding thorough documentation and running internal checks keeps projects on track. In-house testing, even with simple TLC or HPLC, surfaces supplier shortfalls before they grow into full-blown problems. Ultimately, reliable purity isn’t about optics—it’s the backbone of good science and consistent business.
| Names | |
| Preferred IUPAC name | 1-[(2-chlorophenyl)methyl]-1H-pyrrole |
| Other names |
1-(2-Chlorobenzyl)pyrrole 1-(2-Chlorophenylmethyl)pyrrole 2-Chlorobenzylpyrrole |
| Pronunciation | /ˈoʊˌklɔːr.oʊˈbɛn.zɪl waɪˈpiːr.oʊl/ |
| Identifiers | |
| CAS Number | [16619-44-0] |
| 3D model (JSmol) | `JSmol.loadInline("data:text/plain;base64,CSC1-(O-Chlorobenzyl)-1H-Pyrrole;O=C1C=CC=CN1CC2=CC=CC=C2Cl;;0;;")` |
| Beilstein Reference | Beilstein 16 699 |
| ChEBI | CHEBI:131786 |
| ChEMBL | CHEMBL1310409 |
| ChemSpider | 141730 |
| DrugBank | DB08495 |
| ECHA InfoCard | 03dbe433-5b99-4075-81a0-996843c570f7 |
| EC Number | EC 239-424-0 |
| Gmelin Reference | 91939 |
| KEGG | C19134 |
| MeSH | D030594 |
| PubChem CID | 23857890 |
| RTECS number | GQ3150000 |
| UNII | A803X2WA63 |
| UN number | NA1993 |
| Properties | |
| Chemical formula | C11H10ClN |
| Molar mass | 219.69 g/mol |
| Appearance | Yellow Liquid |
| Odor | aromatic |
| Density | 1.17 g/cm3 |
| Solubility in water | Insoluble |
| log P | 2.8 |
| Vapor pressure | 3.2X10^-3 mm Hg at 25°C |
| Acidity (pKa) | pKa = 17.0 |
| Basicity (pKb) | 10.24 |
| Magnetic susceptibility (χ) | -64.96×10^-6 cm³/mol |
| Refractive index (nD) | 1.6010 |
| Viscosity | Viscous liquid |
| Dipole moment | 2.95 Debye |
| Thermochemistry | |
| Std molar entropy (S⦵298) | 232.4 J·mol⁻¹·K⁻¹ |
| Pharmacology | |
| ATC code | N05CM13 |
| Hazards | |
| Main hazards | Harmful if swallowed. Causes skin irritation. Causes serious eye irritation. May cause respiratory irritation. |
| GHS labelling | GHS02, GHS07 |
| Pictograms | GHS07 |
| Signal word | Warning |
| Hazard statements | H302, H315, H319, H335 |
| Precautionary statements | P210, P261, P280, P305+P351+P338, P337+P313 |
| Flash point | > 113°C |
| Lethal dose or concentration | LD50 oral rat 370 mg/kg |
| LD50 (median dose) | LD50 (median dose): 640 mg/kg (rat, oral) |
| NIOSH | SW0325000 |
| PEL (Permissible) | Not established |
| REL (Recommended) | 0.05 ppm |
| Related compounds | |
| Related compounds |
1-(o-Tolyl)-1H-pyrrole 1-(o-Fluorobenzyl)-1H-pyrrole 1-(o-Bromobenzyl)-1H-pyrrole 1-(p-Chlorobenzyl)-1H-pyrrole 1-Benzyl-1H-pyrrole 1-(o-Chlorophenyl)-1H-pyrrole |
