cis2pentenal

Cis-2-pentenal is an organic compound with the chemical formula C5H8O. It is an aldehyde, specifically a branched-chain aldehyde, and is a structural isomer of trans-2-pentenal. The "cis" designation refers to the spatial arrangement of the hydrogen atoms on the carbon chain, where the hydrogen atoms are on the same side of the double bond.

Cis-2-pentenal is a colorless liquid at room temperature and has a characteristic aldehyde odor. It is soluble in organic solvents such as ethanol and ether, but insoluble in water. The compound is used in various chemical syntheses, particularly in the production of other organic compounds and as a precursor in the synthesis of pharmaceuticals and agrochemicals.

The synthesis of cis-2-pentenal typically involves the oxidation of the corresponding alcohol, 2-methylbut-2-en-1-ol, using an oxidizing agent such as pyridinium chlorochromate (PCC) or chromium trioxide (CrO3). The reaction proceeds via a hydride shift mechanism, where the hydrogen atom migrates to the carbonyl carbon, resulting in the formation of the aldehyde.

Cis-2-pentenal is also a useful intermediate in the synthesis of various natural products and biologically active compounds. Its reactivity and versatility make it a valuable reagent in organic chemistry. However, due to its potential health and environmental hazards, proper handling and disposal procedures should be followed when working with this compound.