TRANS-2-NONENAL

(1), the synthesis of -phenylthio-nonenal
Take n-nonynyl (0.12 g, 1 mmol), phenylthiophenol (2a) (0.33 g, 3 mmol) was dissolved in chloroform, the reaction was carried out at 20 ; the reaction was tracked by TLC until it was completely finished; the crude product obtained at the end of the reaction was separated by column chromatography (petroleum ether: ethyl acetate=10:1), the target product was obtained (yield 84%);

(2) Synthesis of target product (E)-2-nonenal

Weighing -phenylthio-nonenal (3f) (0.25 g, 1 mmol) was dissolved in 10 mL of dichloromethane, and aqueous hydrogen peroxide (0.22 g, 2 mmol, 30%) was added drop by drop at 0 with continued stirring for 3 h. Ten milliliters of water was added, and the reaction was carried out under 30 with stirring. The reaction was stirred and followed by TLC until the complete completion of the reaction; after the reaction, the reaction solution was poured into a saturated solution of sodium bicarbonate, the aqueous phase was extracted by adding dichloromethane, the organic layers were combined, washed by adding saturated solution of sodium bicarbonate, and then dried and concentrated with anhydrous magnesium sulfate. The crude product was separated by column chromatography (petroleum ether:ethyl acetate=10:1) to obtain the target product (E)-2-nonenal (83% yield)