But-2-enoyl chloride

But-2-enoyl chloride is an organic chemical compound with the molecular formula C4H5ClO and CAS number 10487-71-5. It belongs to the family of acyl chlorides, featuring an unsaturated four-carbon chain with a double bond at the 2-position and a highly reactive carbonyl chloride functional group. With a molecular weight of 104.53 g/mol, this compound is primarily used as an intermediate in organic synthesis and chemical manufacturing processes.

But-2-enoyl chloride is typically a colorless to pale yellow liquid at room temperature with a pungent, acrid odor characteristic of acyl chlorides. The compound is highly reactive due to its acyl chloride functionality and readily hydrolyzes in the presence of moisture, releasing hydrogen chloride gas. It is soluble in organic solvents but reacts violently with water and alcohols, making it moisture-sensitive and requiring anhydrous handling conditions.

But-2-enoyl chloride serves as a key intermediate in organic synthesis, particularly in pharmaceutical and fine chemical manufacturing. It is commonly used for acylation reactions to introduce the but-2-enoyl group into various molecules, enabling the synthesis of esters, amides, and other derivatives. The compound finds applications in the production of active pharmaceutical ingredients, agrochemicals, and specialty chemicals where selective acylation is required.

But-2-enoyl chloride requires careful handling with appropriate personal protective equipment including chemical-resistant gloves, safety goggles, and protective clothing. Work should be conducted in a well-ventilated area or under a fume hood to avoid inhalation of vapors or hydrogen chloride gas released upon hydrolysis. Avoid contact with water, alcohols, and other nucleophiles that can cause violent reactions, and ensure all equipment is dry before use.

But-2-enoyl chloride must be stored in a cool, dry place away from moisture, heat sources, and incompatible materials. The container should be tightly sealed and made of compatible materials resistant to acyl chlorides. Keep away from water, alcohols, amines, and strong bases which can react violently. Storage areas should be well-ventilated and equipped with appropriate spill containment measures to handle potential leaks safely.

In case of skin contact with but-2-enoyl chloride, immediately remove contaminated clothing and flush the affected area with plenty of water for at least 15 minutes. For eye contact, rinse immediately with water and seek medical attention. If inhaled, move to fresh air and seek medical help if breathing difficulties occur. In case of ingestion, do not induce vomiting and seek immediate medical attention while providing the safety data sheet to medical personnel.

But-2-enoyl chloride waste must be disposed of according to local and national hazardous waste regulations. The compound should be treated as hazardous waste and handled by licensed waste disposal companies. Small quantities can be carefully hydrolyzed under controlled conditions to convert the acyl chloride to the corresponding carboxylic acid, but this should only be done by trained personnel with proper safety equipment and neutralization procedures in place.

But-2-enoyl chloride is classified as ADR Class 8 (corrosive substances) with Packing Group II for transport purposes. It must be packaged in UN-approved containers suitable for corrosive liquids and properly labeled with appropriate hazard placards. Transport vehicles must comply with ADR regulations for Class 8 materials, including proper ventilation and emergency equipment. Shipping documentation must include the correct UN number and hazard classification information.

But-2-enoyl chloride is subject to various chemical regulations including REACH registration requirements in the European Union for commercial use. While not classified as a Substance of Very High Concern (SVHC), it must comply with CLP regulation for classification, labeling, and packaging. Users must ensure proper risk assessment and safety measures are in place according to the chemical safety report and exposure scenarios provided by suppliers.

But-2-enoyl chloride is available through OYSI, a leading European distributor of specialty chemicals and intermediates. OYSI provides high-quality but-2-enoyl chloride to pharmaceutical, chemical manufacturing, and research institutions across Europe. As an established chemical distributor, OYSI ensures proper handling, packaging, and regulatory compliance for all shipments, supporting customers with technical expertise and reliable supply chain management for their chemical requirements.