4677-20-7

General procedure for the synthesis of 4-bromoethyltetrahydropyran from the compound (CAS: 428871-01-6): lithium bromide (29.7 g, 56.9 mmol) was added to a stirred solution of ethyl 2-(4-oxo)methanesulfonate (11.9 g, 56.9 mmol) in anhydrous acetone (300 mL). The reaction was refluxed under nitrogen (N2) atmosphere for 5 hours. Upon completion of the reaction, the acetone was removed by rotary evaporation, water (150 mL) was added, and the mixture was extracted with dichloromethane (2 x 100 mL). The organic extracts were combined, dried with potassium carbonate (K2CO3), filtered and concentrated by rotary evaporation to give a light brown oil. The crude product was purified by distillation (65 °C, 0.2 mmHg) to give 8.06 g of colorless oil in 73.3% yield.

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