In the late nineteenth century, organic chemists were tackling the puzzle of aromatic substitution. 2-Amino-p-Cresol first showed up on their radar through curiosity-driven experiments involving coal tar derivatives. Synthetic dyes brought crowds of researchers to similar compounds, because aromatic amines offered dramatic changes to textile colors. Not long after, pharmaceutical researchers found that small tweaks on benzene rings led to new activities in pain management and anesthesia. For more than a century, 2-Amino-p-Cresol continued cycling through dye houses, pharmaceutical labs, and chemical plants. Technical progress in chromatography, mass spectrometry, and crystallography in the twentieth century helped untangle the property and behavior of this compound, opening the door to new uses and a better understanding of its safety and reactivity.
2-Amino-p-Cresol stands as a well-recognized member of the aminophenols, meaning it combines both an amino and a hydroxy functional group on a methyl substituted benzene ring. It gives off a faint yet distinct aroma, and in pure form delivers pale crystalline solids that dissolve in water and ethanol. Researchers value its chemical structure for both its reactivity and flexibility; the molecule serves as a starting block for larger, more complicated molecules in the fields of dye synthesis and pharmaceuticals. Its popularity in the dye and pigment trade comes from the way it readily forms coupling products and offers strong color stability. Its availability as a reagent stems from decades of demand by labs and manufacturers seeking reliable chemical building blocks.
2-Amino-p-Cresol appears as a cream-colored crystalline solid at room temperature, with a melting point just over 120°C. It maintains outstanding solubility in most alcohols, and moderate solubility in water. Because the amino and hydroxyl groups sit on opposite sides of the benzene ring, the molecule acts as both a base and a weak acid, interacting strongly with both acids and oxidizers. A methyl group on the para position offers subtle electronic effects that influence how the molecule participates in further reactions, especially as a nucleophile or an intermediate in oxidations and substitutions. Lab experience shows it oxidizes quickly in air, with solutions turning brown over time, which means storage calls for airtight, light-shielded containers.
Most suppliers deliver 2-Amino-p-Cresol at a purity of 98% or above, often certified by high-performance liquid chromatography analysis. The product ships in glass or sealed polyethylene-lined containers, marked with chemical identification numbers from global regulatory bodies such as CAS (95-84-1), UN shipping numbers, hazard pictograms, and storage advice. Labels spell out the presence of aromatic amine and phenol functional groups, taking into account both chemical reactivity and toxicity. At the laboratory level, details such as melting point, bulk density, and residual solvent levels drive decisions about suitability for specific applications.
The industrial prep of 2-Amino-p-Cresol doesn’t involve only one approach. Classic organic synthesis routes rely on nitration of p-cresol to form the corresponding nitro derivative, followed by reduction using hydrogenation or tin and hydrochloric acid. Several refinements have appeared over decades to improve selectivity and purity, including catalytic hydrogenation in controlled reactors, reducing risks from toxic offgassing. Laboratory workers preparing small quantities often choose milder conditions, relying on sodium sulfide for reduction. Alternative green chemistry processes target waste minimization and solvent recovery, though catalysts remain sensitive, and side-products keep recycling engineers on their toes.
Working with 2-Amino-p-Cresol in synthetic chemistry means access to both phenol and aniline chemistry on one ring. The amino group opens the door for diazotization, leading to azo dyes or further coupling reactions with phenols and naphthols, giving rise to broad color palettes and complex molecular frameworks. Electrophilic aromatic substitution at the available ortho and meta positions can install sulfonic acid groups or alkyl chains, further expanding the property set. O-alkylation and acylation reactions go smoothly under mild basic or acidic conditions, allowing the introduction of functional groups for downstream coupling. In medicinal chemistry projects, researchers attach side chains or ring systems, tweaking activity for enzyme inhibition, antimicrobial strength, or improved metabolic stability. Over the years, 2-Amino-p-Cresol’s adaptability has placed it at the center of new investigations into advanced polymer backbones and surfaced-modified nanoparticles for sensing and delivery.
Over decades, the chemical industry has given multiple names to 2-Amino-p-Cresol. Common synonyms include p-Cresidine, 2-Hydroxy-4-methylaniline, and 4-Methyl-2-aminophenol. Trade names occur less frequently; when they do, the naming references function, such as dye intermediate RC-2 or methylaminophenol. Purchasers need to pay close attention to structure, as other aminophenols with different substitution patterns deliver quite different chemical behaviors and safety profiles. The CAS registry keeps a stable identifier for tracking regulatory approvals and research publications, which reduces mix-ups during communication between suppliers, storage staff, and lab technicians.
Experience has shown that handling aromatic amines and phenols calls for care and respect for toxicity. 2-Amino-p-Cresol, like many of its relatives, can cause skin, eye, and respiratory irritation, and in higher doses brings toxicity risks both acute and chronic. The compound is absorbed through the skin, so gloves and goggles are standard. Contact with strong oxidizers or acids can cause violent reactions or noxious fumes, requiring good ventilation and isolation of workstations. Labels carry hazard codes for acute toxicity and potential environmental harm. Industrial operations must handle waste streams containing 2-Amino-p-Cresol with extra care, using chemical neutralization and filtration to prevent water contamination. Regular training helps lab personnel avoid exposure, and safety data sheets require updates to capture evolving evidence from toxicological studies.
The world of aromatic dye chemistry has depended on 2-Amino-p-Cresol for much of the past century, especially for manufacturing azo and sulfur dyes for wool, silk, and synthetics. The molecule’s twin functional groups make it a handy starting point for more complicated dyes that give stable, intense colors under harsh washing and UV light. In the pharmaceutical world, the molecule finds use in intermediates for analgesics, antipyretics, and even as precursors to anesthetics. Regulatory changes and demand for eco-friendly compounds shrink the application window in personal care and laundry products, but areas like organic electronics and sensing technologies keep discovering new uses. Laboratory techniques applying 2-Amino-p-Cresol for analytical assays, such as redox titrations and trace metal detection, show its versatility extends far beyond the factory floor.
Ongoing research tracks not only the synthesis of new derivatives but improvements in yield, selectivity, and environmental footprint for large-scale production. Green chemistry teams target catalytic steps with lower energy demand and less waste, experimenting with immobilized catalysts and water-based solvents. Medicinal chemists keep probing modifications on the aminophenol backbone, seeking new antifungal, anticancer, or enzyme inhibitor scaffolds. A steady flow of papers covers surface modifications using 2-Amino-p-Cresol for sensor development, bioconjugation protocols, and nanomaterial fabrication. Regulatory shifts in acceptable dye intermediates drive chemistry teams back to the drawing board for alternatives that offer the same color stability and processability with lower environmental impact. Graduate schools lean on this compound for student training in classical synthetic methods, keeping technical knowledge alive for the next generation of chemists and chemical engineers.
Studies completed over several decades show that aromatic amines often present more than just skin-level hazards. Experimental work in rats and mice highlights the risk of kidney and liver effects after repeated high exposures, and data suggest some risk of mutagenicity from breakdown products created inside the body. Environmental research tracks the way aminophenol residues persist in water or soil, sometimes sticking to sediment or carrying into plant roots. Early data set regulatory limits for workplace airborne concentration, based on observed effects in animal studies and accident case histories. Toxicologists call for continual review of old studies, since even small tweaks in downstream usage can alter risk factors for workers and the environment, especially when dealing with large-scale dye production or pharmaceutical manufacturing. Industry updates on safety data sheets remain part of compliance routines to keep pace with changing evidence from both public and private sector health agencies.
The pressures of sustainability and regulatory constraints push every player in the field to revisit compounds like 2-Amino-p-Cresol. As dye houses shift away from fossil-based sources, demand moves toward recycled or bio-based aromatic substrates, and researchers keep searching for recyclable catalysts and safer process water cycling. Analytical labs continue using modified aminophenol backbones for probe design in rapid diagnostics, environmental sensors, and microelectronic patterning. As pharmaceutical lead optimization algorithms uncover new uses for aminophenols, each iteration brings further scrutiny for toxicity, metabolism, and environmental persistence. Early signs suggest continued, though perhaps reduced, roles for 2-Amino-p-Cresol in its classic industries, with fresh interest from research teams hunting for new classes of colorants, specialty materials, and bioconjugation reagents that blend safety with performance. Factories and labs chasing profit and safety will hone practices for cleaner production, more robust monitoring, and improved downstream treatment to limit worker and environmental risk, ensuring this century-old compound remains productive, safe, and aligned with what the community expects from modern chemistry.
2-Amino-P-Cresol might sound like something you’d only find in chemistry research, but it touches several corners of daily life—especially where color and medicine cross paths. This compound comes from the group known as aromatic amines. That means it’s built for more than just storage on a shelf. Its properties let chemists and manufacturers shape new products, some of which end up in common goods.
Dig into any deep research on colorants, and 2-Amino-P-Cresol shows up. It’s often used as an intermediate in making dyes, especially for textiles and hair. The molecule allows for the design of colors that hold up under repeated washing or strong light. Factories depend on compounds that produce reliable color results and don’t break down easily. This need for stability keeps manufacturers coming back to 2-Amino-P-Cresol and similar ingredients.
People might not notice the connection every time they buy a colored shirt or apply temporary hair color, but without this compound, those vibrant shades could fade faster or trigger more skin irritation. Researchers have tested this ingredient and set safety levels for consumer products. Anyone working around industrial dyes has to know about the health risks of aromatic amines, and 2-Amino-P-Cresol sits on regulatory lists in places like the EU and the U.S. It takes strict oversight to make sure it’s handled in safe amounts.
The same chemical structure that makes 2-Amino-P-Cresol useful in colored goods has drawn the attention of pharmaceutical labs. Chemists use it as a building block to synthesize more complex drugs. Some medicines—especially those targeting infections or inflammation—depend on related aromatic rings. Everything boils down to how the molecule can link to others and create new bonds inside a drug formula.
Labs often use 2-Amino-P-Cresol as a starting material, testing new combinations that could eventually treat disease. That process doesn’t just happen in one country. Global health research uses such compounds in both academic and for-profit work. The hunt for better drugs always needs new building blocks, but researchers keep their eyes on toxicity studies and safe handling at each step.
Any aromatic amine deserves close attention, and 2-Amino-P-Cresol is no exception. Once released into wastewater or handled without the right gear, these compounds can create bigger problems—sometimes affecting water supplies or worker health. You can’t brush aside chemical safety in manufacturing. Factories need up-to-date filtration systems and protective measures for workers. Doctors and scientists also study potential long-term effects with every new chemical that finds its way into consumer goods or research stockrooms.
The answer isn’t to scrap these chemicals from industry, but to do the hard work of continuous monitoring and finding safer substitutes where needed. Future solutions will probably rely on green chemistry—methods that reduce hazardous waste and limit exposure. Keeping safety and transparency at the center of chemical use gives people more confidence in the products on shelves and puts businesses on the right side of health regulations.
2-Amino-p-cresol stands out in the world of organic chemistry thanks to its structure and functional groups. The name says a lot: it’s a derivative of cresol, which means it’s rooted in the benzene ring with a methyl group attached (that's the “cresol” part). The “2-amino” part means there’s an amino group (–NH2) connected to the same ring, but at the position right next to the methyl. The “p” in p-cresol points to the “para” orientation of the –OH and –CH3 groups across from each other on the benzene ring.
The structure combines three groups on a benzene ring:
From a drawing, you’d see six carbons forming a hexagonal benzene ring. The –OH hugs the first carbon, –NH2 sticks to the next, and the –CH3 shows up at the fourth spot. This arrangement matters a great deal in how the molecule reacts and what it can be turned into. A close look at the bonds and groups reveals how organic chemistry sometimes brings together features that deliver qualities both simple and powerful.
Once you've dived into a bit of lab work, you notice how small tweaks in the position of groups like –NH2 and –OH can turn a harmless compound into something reactive. 2-Amino-p-cresol acts as more than an academic curiosity. It becomes a building block for dyes, pharmaceuticals, and stabilizers for plastics. Its functional groups allow chemists to hook on other useful bits, which means it keeps showing up whenever a company needs a handy starting point for new materials or medicines. The orientation also helps control the molecule’s solubility in water and how it bonds with others in solution.
Data from the chemical supply chain shows how molecules like this slide into the production of hair dyes and antioxidants. The amino and hydroxyl groups make it a good candidate for coupling reactions, and industries lean into that, scaling up reactions by the kilo. Published studies in journals reveal 2-amino-p-cresol’s role as a key ingredient in synthesis that brings efficiency but demands careful handling because the functional groups increase reactivity.
Having worked around organic compounds, I know many workers feel uneasy about exposure to aromatic amines. Research points out health risks—skin sensitivity, potential toxicity, even connections to longer-term conditions. Factories dealing with aromatic intermediates face strict regulations, given how fast mistakes can lead to headaches, allergies, or worse. Calls for regular monitoring and proper personal protection aren’t just a checklist item. Everybody from shift workers to lab chemists sees that safety gear and fume hoods stop trouble before it starts. Studies from occupational health demonstrate clear benefits from education, labeling, and substitution with less hazardous analogs where possible.
Newer synthetic methods keep finding ways to make and use 2-amino-p-cresol with less waste and fewer accidents. Most progress happens by substituting hazardous solvents with greener options and automating the trickiest steps to limit direct contact. Sharing best practices and investing in training goes a long way to reducing incidents and ensuring better long-term outcomes for those involved with these chemicals. The focus always returns to proper structure identification and honest respect for how a few groups on a benzene ring can make such a difference in both chemistry and workplace safety.
2-Amino-P-Cresol often finds its way into labs and factories thanks to its key role in making dyes and chemicals. The substance pops up in permanent hair dyes and sometimes crops up in research labs for testing antioxidant properties. Its chemical relatives shape all sorts of products—cleaners, inks, and even medicines.
I remember walking through the chemical storage at a university lab and noticing the strong caution labels slapped on the bottles containing cresol compounds. 2-Amino-P-Cresol is no exception—handling it with bare hands never crossed my mind. The facts back this up. Skin and eye irritation show up fast. Exposure can trigger allergic reactions, and those with sensitive skin end up in the nurse’s office too often.
A toxicology review shows that substances like 2-Amino-P-Cresol carry a risk of short-term symptoms—burning, redness, even headaches from fumes. Chronic exposure further complicates the story. Some health agencies eye these cresol amines with suspicion for their potential link to more serious issues. The International Agency for Research on Cancer points out that aromatic amines might contribute to a higher cancer risk in lab animals. Transferring those results to humans takes more proof, but it sets off alarm bells for workers and researchers alike.
From my years around chemical labs, rules like wearing gloves, goggles, and masks never seem like overkill. Fact is, one spilled bottle or stray droplet could mean rash or burns on the skin. For folks in hair salons using dyes with these ingredients, skin contact is a daily concern, and chemical-resistant gloves become part of the routine.
Research from occupational safety organizations, such as the National Institute for Occupational Safety and Health (NIOSH), underlines the importance of solid ventilation and protective gear. Airborne particles from handling or mixing increase the risk to lungs and eyes. No one wants that sort of reminder stuck with them after a shift.
Companies and supervisors carry an even weightier responsibility. They track spills and protect water sources. Spills of 2-Amino-P-Cresol may do more than hurt people—they can harm fish and other aquatic life if washed into drains. Waste management plays a key role. Using certified disposal services and labeled waste bins in the shop or lab keeps accidents out of the local river or water plant.
Training stands out as the most useful tool. I recall new teammates getting a hands-on drill about what to do during a chemical splash. Simple steps—rinsing under water, swapping out contaminated clothes, reporting the incident—stick with people longer than a dusty manual ever will.
Better access to safety data sheets makes a difference. Labels in plain language help everyone, not just people with years of chemistry under their belt. Tech solutions such as real-time air sensors and smart storage cabinets catch tiny leaks and volatility.
Stricter rules can push companies to use less toxic ingredients in their blends. Regulators and consumer groups both have a part to play, watching for long-term health effects. My time in educational labs showed how group responsibility—everyone looking out for each other—raises awareness and lowers accidents.
2-Amino-P-Cresol deserves the respect any hazardous chemical gets. Respecting science-backed guidelines means more people go home safe, and fewer long-term health worries nag the back of the mind. Working with these substances, vigilance and common sense make all the difference.
2-Amino-P-Cresol may not be an everyday household name, but in labs and industries, it's got a specific reputation. This organic compound, like a lot of similar aromatic amines, brings both usefulness and risk. Experts know it can oxidize, degrade, and react with air and moisture if left out in the open for too long. That's not just a minor inconvenience—degradation means researchers or technicians can't trust their results. A recent recall of a batch of aromatic amines due to improper capping highlights how just a little oxygen sneaking in can ruin a whole lot of effort and money. Plus, a breakdown can produce hazardous by-products. That’s not an urban lab legend; it goes straight into the safety data sheets and practical training at the bench.
Anyone working with 2-Amino-P-Cresol knows not to tuck it away next to open windows or on a sunny shelf. Common sense and scientific literature both stress a cool, dry spot—think 2 to 8 degrees Celsius, ideally in a lab fridge or a climate-controlled cabinet. Humidity and warm conditions speed up unwanted reactions, and it doesn’t take much for moisture from the air to make its way inside poorly closed bottles.
Even in a locked cabinet, the type of container plays a big part. Dark amber glass bottles block out the light, which helps keep the compound steady over time. I remember once switching a brown bottle to clear plastic just for easier visibility during an inventory—bad idea. Within weeks, subtle changes in color and a faint chemical smell tipped us off that something had shifted. We tossed the whole bottle and went back to opaque glass, keeping lids tight and seals uncompromised.
If you store 2-Amino-P-Cresol around strong oxidizers, acids, or even chlorine-based cleaning solutions, you’re asking for trouble. Cross-contamination—sometimes as minor as a spilled drop—can spark off tiny, hard-to-see reactions that slowly taint a whole batch. Grouping chemicals by class is more than a textbook suggestion. Mixing containers of incompatible chemicals on a single shelf once ruined half a lab’s inventory because the shelf above held acids and spilled fumes down onto the aminophenols below. These small organizational habits aren’t just tidiness—they protect expensive materials and keep people safe.
Good labeling gets overlooked until something goes wrong. Label every new bottle with the arrival date and the initials of whoever received it. Once opened, mark it as opened, and note the date. This practice tracks shelf life in real time. One bad experience with a forgotten, two-year-old bottle reminded me that even a sturdy freezer can’t turn back the chemical clock. Regular audits and clear records allow labs to spot out-of-date or damaged stock before it leads to costly errors or safety risks.
Stories circulate about students or lab techs who forget the basics and face consequences—a swollen bottle, a strange smell, a little more corrosion on metal shelving than expected. One case in a university lab involved a single missed cabinet cleaning: months later, a leaking jar was found, and corrosion stains etched themselves into the woodwork. The lesson hit home: good storage isn’t just about following rules. It’s a hands-on way to prevent property damage, health hazards, and financial loss.
Smart storage for 2-Amino-P-Cresol isn’t the most exciting job on a chemist’s to-do list. But it makes real impacts on lab budgets, safety, and research quality. Cool, dry, dark, and organized—that’s the method that keeps science working, keeps people safe, and makes sure no one gets blindsided by a surprise chemical event.
Chemistry doesn’t care for buzzwords or fancy filler. It cares for measurements. The molecular weight of 2-Amino-P-Cresol — 123.15 grams per mole — isn’t just a number, it’s a tool in every lab and on every shelf where this compound shows up. Safe handling, dosing, and even storage, all depend on knowing this figure. If a lab tech pours out a chemical and doubts that weight, entire batches or jobs could run off the rails. In pharmaceutical work or dye synthesis, miscalculating by even a few decimal points means wasted effort or even danger.
I’ve measured out chemicals both for undergrad experiments and in my own kitchen for home soapmaking, and believe me, getting the numbers wrong in either case ends up as a mess, if not a safety risk. For 2-Amino-P-Cresol, the math isn’t rocket science:
Sum those up and you’ve got 123.14 g/mol, but manufacturers round to 123.15. Tiny decimal points like that carry weight in practical work. Measuring out 10 grams with old glassware, you might think it’s overkill. Yet I’ve watched reactions stall and colors fade because someone used a rounded-off number from memory instead of checking the official calculation. Data slips, batches get scrapped, money and trust go down the drain.
The weight doesn’t just matter in the lab. Safety data sheets use this number to guide everything from exposure limits to spill cleanups. Regulators writing guidelines for wastewater treatment use it to model environmental breaks and impacts. For anyone tracking potential hazards, estimating how much might vaporize or dissolve into water starts with the molecular weight. I’ve followed enough protocols to know that shortcuts on paperwork create long-term headaches. Imagine miscalculating the amount left after a spill, just because of a lazy molecular weight estimate. Now multiply that by the thousands of factories and research labs using similar compounds.
Every scientist, production worker, or safety officer working with chemicals learns to trust, but verify — especially when it comes to measurables like mass. The switch from habitual guesswork to evidence-based handling has saved lives and money. This shift picks up steam thanks to voices from health researchers and environmental monitors who depend on accuracy, not just in labs but across the industries that rely on compounds like 2-Amino-P-Cresol.
If you’re working with this compound, trust in the foundation that precision brings. Make the calculation explicit on every datasheet, every bottle label, every electronic database. Tech keeps changing, but the respect for numbers — and the discipline to use them — keeps everyone safer and projects on track.
| Names | |
| Preferred IUPAC name | 4-Amino-2-methylphenol |
| Other names |
2-Amino-4-methylphenol 2-Hydroxy-5-methylaniline 2-Hydroxy-p-cresidine 2-Hydroxy-5-methylbenzenamine |
| Pronunciation | /tuː-əˈmiːnoʊ-piː-ˈkriːsoʊl/ |
| Identifiers | |
| CAS Number | 120-23-0 |
| Beilstein Reference | 1209244 |
| ChEBI | CHEBI:18941 |
| ChEMBL | CHEMBL76274 |
| ChemSpider | 77524 |
| DrugBank | DB08234 |
| ECHA InfoCard | ECHA InfoCard: 100.010.093 |
| EC Number | 226-356-2 |
| Gmelin Reference | 79203 |
| KEGG | C06657 |
| MeSH | D000584 |
| PubChem CID | 86698 |
| RTECS number | GX8225000 |
| UNII | 0I4CWI3W8K |
| UN number | UN2811 |
| CompTox Dashboard (EPA) | DTXSID1052096 |
| Properties | |
| Chemical formula | C7H9NO |
| Molar mass | 123.15 g/mol |
| Appearance | Light brown solid |
| Odor | Odorless |
| Density | 1.110 g/cm3 |
| Solubility in water | Slightly soluble in water |
| log P | 1.12 |
| Vapor pressure | 0.0188 mmHg at 25°C |
| Acidity (pKa) | 10.36 |
| Basicity (pKb) | 8.1 |
| Magnetic susceptibility (χ) | -58.0 x 10^-6 cm³/mol |
| Refractive index (nD) | 1.659 |
| Viscosity | 1.181 cP (25°C) |
| Dipole moment | 1.51 D |
| Thermochemistry | |
| Std molar entropy (S⦵298) | 138.7 J·mol⁻¹·K⁻¹ |
| Std enthalpy of formation (ΔfH⦵298) | -40.2 kJ/mol |
| Std enthalpy of combustion (ΔcH⦵298) | -3682 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 + H315 + H319 + H335 |
| Precautionary statements | Precautionary statements: P261, P280, P305+P351+P338, P309+P311 |
| NFPA 704 (fire diamond) | 2-1-0 |
| Flash point | 126°C |
| Autoignition temperature | 515°C |
| Lethal dose or concentration | LD50 (Oral, Rat): 1750 mg/kg |
| LD50 (median dose) | 1250 mg/kg (Rat, oral) |
| NIOSH | RG3210000 |
| PEL (Permissible) | Not established |
| REL (Recommended) | REL (Recommended Exposure Limit) of 2-Amino-P-Cresol is: "0.5 mg/m3 |
| IDLH (Immediate danger) | Unknown |
| Related compounds | |
| Related compounds |
2-Amino-m-cresol 2-Amino-o-cresol 2-Amino-4-methylphenol 4-Methylcatechol o-Cresol p-Cresol |
