Crotonaldehyde

2-butenal, C ₄ H ₆ O (70.09). CH ₃ CH=CHCHO. It is synthesized by condensing two molecules of acetaldehyde. It is a colorless liquid with a pungent odor. Its melting point is -76.5 °C, boiling point is 104 °C. Its molecular weight is 0.8715 and its molecular weight is 1.4384. It can be distilled with steam. It easily polymerizes if left standing. It is easily oxidized to crotonic acid. The commercially available product is usually the trans-isomer. [CAS 4170-30-3]

Source: Morikita Publishing "Chemical Dictionary (2nd Edition)" Information about the Chemical Dictionary 2nd Edition

2-butenal，C₄H₆O(70.09)．CH₃CH=CHCHO．アセトアルデヒドを2分子縮合させて合成される．刺激臭のある無色の液体．融点－76.5 ℃，沸点104 ℃．0.8715．1.4384．水蒸気蒸留できる．放置すると容易に重合する．酸化されてクロトン酸になりやすい．市販品は普通はトランス形である．[CAS 4170-30-3]

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