Thiophene-2-Carbaldehyde stands as a staple intermediate in the chemical world, recognized for its unique blend of aromatic stability and reactivity that stems from the thiophene ring fused with an aldehyde group. Products crafted with this compound benefit from a backbone that manages to balance function and versatility. On the shelf, forms range from solid crystals to oily liquids and pale powders, always carrying the sharp, distinct aldehyde note that chemists will know the moment a flask is opened. Its CAS number 98-03-3 is well-established in industry catalogs, and any lab dealing with fine organic synthesis will likely keep a bottle of it in stock at all times.
The structural foundation holds a five-membered thiophene ring bonded to an aldehyde group at the second position, a layout that delivers the molecular formula C5H4OS and a molar mass of roughly 112.15 g/mol. Chemical diagrams draw a planar, rigid structure, where the resonance of thiophene’s sulfur-doped ring supports both electron-rich and electron-deficient reactions. This shape gives it the edge in applications where selectivity and predictable behavior really count, from creating advanced pharmaceutical agents to tuning the properties of high-end materials. Thiophene-2-Carbaldehyde’s density hovers around 1.229 g/cm3, putting it in line with most other substituted thiophenes traded in chemical markets today.
Buyers tend to see Thiophene-2-Carbaldehyde arriving as clear, mobile liquid or as faintly yellow crystals, depending on the batch and storage. It melts at about 6-8 °C and boils in the range of 223-224 °C. The refractive index stands around 1.583 to 1.585. In my experience, handling it without strong ventilation can feel uncomfortable, as the vapor carries a pungency that lingers. Understanding its solubility matters: it dissolves well in most common organic solvents, such as diethyl ether, ethanol, and chloroform, but resists mixing with water. Storage always means cool, dry, dark conditions, away from strong oxidizers and acids—which is just standard best practice for any lab that cares about long shelf life and clean handling.
Specification sheets frequently list purity well above 98%, with key impurities being other oxygenated thiophenes or trace residual solvents from synthesis. For buyers working at industrial scale, such as in pharmaceuticals or electronics, knowing the exact trace contaminants turns crucial, since many products derived from this material end up in higher-value functional ingredients. Standard batch sizes span from hundreds of grams to multiple kilos, packed in sealed metal or amber glass containers to reduce decomposition and moisture uptake. Reading these spec sheets can feel tedious, but small oversights in moisture or metal ions can derail large-scale reactions, so careful sourcing remains paramount. The HS Code associated with Thiophene-2-Carbaldehyde generally reads as 2934.99, grouping it with other heterocyclic compounds in customs documentation.
Thiophene-2-Carbaldehyde plays a big part in synthesizing pharmaceuticals, agrochemicals, dyes, and electronic materials. Its ability to serve as a raw material for various substitutions and couplings means it finds a home in the hands of synthetic chemists aiming to build more complex ring systems or introduce a functional group at a specific position. In the world of electronic materials, derivatized thiophenes help lay the groundwork for conducting polymers and OLED components, where performance depends strongly on the purity and structural integrity of starting chemicals. Over the years, I have seen it requested by both medicinal chemists and materials scientists, a testament to the flexibility and value provided by this specific aldehyde.
While Thiophene-2-Carbaldehyde does not stand out as profoundly dangerous compared with some counterparts, its classification as a hazardous chemical remains clear. Direct exposure causes irritation to eyes, skin, and mucous membranes, especially in poorly ventilated rooms or if splashed on wet hands. Safety data sheets highlight its acute toxicity—swallowing or inhaling leads to nausea or respiratory distress, so I always recommend full lab gear, from nitrile gloves and goggles to fume hoods. Its flash point sits at 99 °C, putting it out of reach of most accidental lab sparks but still deserving respect on busy benches. Waste disposal must go into designated organic solvent drums, never down regular drains, to prevent environmental risks from its persistence and possible effects on aquatic life.
Concerns over environmental and user safety continue to drive efforts in manufacturing and utilization. Innovations in packaging, better chemical labeling, and improved air handling systems take center stage where bulk handling happens, frequently in raw materials warehouses for pharmaceutical or electronics plants. There is a growing push toward greener synthetic alternatives that aim to deliver the same reactivity profile but with lower toxicity, yet those alternatives rarely equal the track record or versatility already established by Thiophene-2-Carbaldehyde. On the practical side, ongoing education for lab staff, clear hazard communication, and more accessible emergency response guidance become essential as this material continues to see widespread use, whether as pure crystals in research settings or as part of large blends in commercial synthesis. Regular audits and investment in analytical quality control tools help labs and manufacturers maintain both safety and product integrity. Making small changes—like switching from open handling to sealed transfer systems—has cut exposure risks in my own lab and sped up work at the same time.
Thiophene-2-Carbaldehyde rarely grabs headlines, yet shifts in raw materials pricing, regulatory demands for purity, and the evolving landscape of end-user industries directly impact its market availability. Tighter rules about residual solvents and traceable supply chains now mean buyers are demanding more transparency from their suppliers, pushing some older producers to refresh their documentation and safety protocols. Supply disruptions—a common headache in recent years as transport routes faced disruptions—remind us just how integrated global chemical commerce has become, and what it means to rely on single-source specialty chemicals for product lines with high stakes. In practice, working closely with trustworthy suppliers and maintaining locally held stocks mitigates risk and ensures research or production runs don’t grind to a halt.
