Propanoicacid,2-formyl-3-oxo-,ethylester is used cyclocondensation reactions for the the preparation of heterocyclic compounds such as polyfunctionally substituted pyridines.
Sodium hydride (2.46 g, 61.5 mmol) was accurately weighed in a dry 100-mL pear-shaped flask. It was washed sequentially with hexane and ether. The washed sodium hydride was suspended in ether (100 mL) and cooled in an ice bath to 0°C. Ethyl formate (24.84 mL, 308 mmol) was added slowly and dropwise, followed by ethyl 3,3-diethoxypropionate (5.98 mL, 30.8 mmol). The reaction mixture was stirred at room temperature for 15 hours to ensure complete reaction. After completion of the reaction, the mixture was slowly poured into ice water and the aqueous phase was washed with ether. The pH of the aqueous phase was adjusted to 1 with dilute hydrochloric acid and subsequently extracted with dichloromethane. The organic phases were combined, washed with saturated aqueous sodium chloride solution, dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure to afford ethyl 2-formyl-3-oxopropanoate (3.29 g, 22.83 mmol, 74.2% yield) as a golden-yellow slurry.
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[2] Patent: US2005/256004, 2005, A1. Location in patent: Page/Page column 31-32
[3] Patent: WO2017/59191, 2017, A1. Location in patent: Paragraph 00441-00443
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