1,2-Ethanedithiol: Down-to-Earth Commentary on Profile, Properties, and Safety

What is 1,2-Ethanedithiol?

1,2-Ethanedithiol, known in the field as EDT or sometimes as ethylene dithiol, stands out for its distinctive smell and practical role in synthesis. Chemists often bump into the dizzying odor long before they spot the clear, oily liquid. Its molecular formula—C₂H₆S₂—tells a lot in a short string of letters. This means each molecule brings two thiol groups to the table, both attached to a neighboring carbon. The presence of both thiols on adjacent carbons makes this small sulfur compound popular for crosslinking reactions and protection strategies in organic chemistry labs. There’s nothing theoretical about the headache you get if someone spills a flask; the scent traces you for hours and lingers wherever an accident occurs.

Physical and Chemical Properties

1,2-Ethanedithiol usually exists as a colorless to pale yellow liquid at room temperature, although it can solidify if stored below freezing. Its density clocks in at around 1.05 g/mL. With a boiling point of roughly 146°C and a melting point near -85°C, the compound handles most lab conditions without turning to vapor or solid under standard environments. You’ll notice it dissolves very little in water but mixes with organic solvents such as alcohols, ethers, or even chloroform. The numbers on the label—CAS number 540-63-6, molecular weight of 94.19, and HS code 29309099—provide quick references for trade and inventory, but the practical information lives in how it behaves on a daily basis. A thioalcohol this reactive often finds use as a raw material for pharmaceuticals, or as an intermediate in the flavor and fragrance sectors where sulfur notes lend unique character. Still, anyone who’s opened a bottle won’t confuse it with vanilla extract.

Structure and Specification

Peering at a model, you’ll count each sulfur atom bonded to its respective carbon, separated by a two-carbo chain. Sulfur atoms sit at each end, creating a molecule that bridges two reactive sulfhydryl groups. This arrangement gives 1,2-ethanedithiol much of its bite and utility. It isn’t rare to see this compound described in forms ranging from technical grade to high-purity versions for analytical or synthesis work, often described as liquid or crystalline materials. Most labs seek it in liquid form due to the simplicity for transfer and measurement, though you can push it into a solid under the right chilly conditions. The practical experience of working with the neat liquid—the way it coats glass, the trace residue—brings home the need for careful handling and tight caps.

Product Forms: Flakes, Powder, Pearls, Liquid, and Crystal

As a specialty chemical, 1,2-ethanedithiol almost always lands on benches as a liquid. You won’t find it in flake or pearl form stocked on regular shelves, but specialized setups might pelletize it for dosing in manufacturing. The standard form, though, is a volatile, oily liquid. For those pushing boundaries in research, small vials of high-purity EDT appear as either viscous liquids or soft crystals if cooled below standard freezing points. Storage temperature sometimes marks the difference, with material solidifying in cold climates or refrigerated labs. Most storage bottles carry more warning than marketing—nobody confuses EDT with a safe-to-handle powder like sodium acetate.

Density, Liter Measurement, and Material Handling

Getting precise density right matters for both mixing calculations and shipping. A technician will find that 1,2-ethanedithiol registers slightly heavier than water. Pouring a liter gives you just over a kilogram, a small but important detail when a reactions calls for exact stoichiometry. Many commercial shipments label the density plainly—1.05 g/mL—and those ordering drums or even small bottles need to plan for both volume and weight. Handling remains the trickiest part. Spills shouldn’t ever get mopped with bare towels, and anyone who splashes it on their clothes knows not to ride an elevator with coworkers afterwards. It sinks into gloves unless the right grade gets chosen; disposable nitrile gloves provide decent protection, but double-gloving stands out as good practice for frequent handling.

Safety, Hazard Information, and Toxicity

Many underestimate just how hazardous 1,2-ethanedithiol can get. The gnawing odor signals more than unpleasantness. Both physical and inhalation hazards exist—strong eye and respiratory irritation, skin burns, and headaches that linger if not enough ventilation is used. The Material Safety Data Sheet (MSDS) spells out its dangers in detail, pointing to acute and chronic toxicological effects. People assigned to handle this chemical put on splash goggles, gloves, lab coats, and work under hoods, never in open labs. Direct contact should be avoided, spills neutralized with appropriate absorbent material, and work areas aired out thoroughly after any transfer or mixing. Disposal doesn’t go in the regular trash—hazardous waste procedures stop this compound from showing up in places it shouldn’t.

Use as Raw Material and Chemical Applications

Chefs have their secret ingredients. For chemists and industry operators, 1,2-ethanedithiol plays a similar role, kicking off reactions that lead to flavors, ligands, or specialty pharmaceuticals. The dual thiol groups make it a go-to for building complex molecules, especially where dithiol units get used for creating links or chelating certain metals. Scent specialists might get interested due to its sulfurous qualities, but most applications turn up in manufacturing where few people need to experience its smell directly. Even as a raw material, regulations watch each shipment, ensuring that those who buy it have valid uses and know what they're bringing in.

Challenges and Responsible Solutions

Personal experience shows that mishandling EDT costs more than downtime and a headache. Once, an unexpected leak inside a poorly ventilated fume hood sent staff running, the whole building nearly cleared for hours to scrape away contaminated glassware. The lesson sticks: never underestimate either the evaporative potential or the staying power of the compound’s smell and hazard. Investing in vented storage cabinets, handling training, and spill kits proves cheaper than a day of lost work or emergency calls. Emphasizing strict safe work procedures, proper storage in ventilated, clearly labeled containers, and precise disposal strategies prevents both health hazards and cross-contamination. For research and industry outfits buying EDT, sourcing from reliable suppliers guarantees product purity, verified specs, and correct documentation—including HS code for customs and international transport. Simple steps make handling a chemical like 1,2-ethanedithiol much safer and keep everybody healthier in the long run.