Synthesis
General procedure for the synthesis of 4-bromo-2-methyl-2-butanol from ethyl 3-bromopropionate and methylmagnesium bromide: To a solution of ethyl 3-bromopropionate (0.2 g, 1.2 mmol) in tetrahydrofuran (THF, 5 mL) was slowly added methylmagnesium bromide (2.4 mL, 2.4 mmol) at 0°C. The reaction mixture was stirred continuously until a thin layer chromatography (TLC) analysis showed complete consumption of the raw material. The reaction mixture was stirred continuously at 0°C until thin layer chromatography (TLC) analysis showed complete consumption of the raw material [Unfolding agent: petroleum ether/ethyl acetate (3:1), Rf value of the product was 0.3]. Upon completion of the reaction, the reaction was quenched with aqueous ammonium chloride (2 mL) at 0°C. The reaction mixture was extracted with ethyl acetate and water by partitioning. The organic layers were combined, dried with anhydrous sodium sulfate, filtered and concentrated to give the crude product. The crude product was purified by column chromatography using petroleum ether/ethyl acetate (3:1) as eluent to give 4-bromo-2-methyl-2-butanol (0.15 g, 75.1% yield) as a yellow oil.
References
[1] Patent: WO2014/143799, 2014, A2. Location in patent: Page/Page column 403
[2] Bioorganic and Medicinal Chemistry, 2001, vol. 9, # 2, p. 525 - 535
[3] Journal of Organometallic Chemistry, 1973, vol. 47, p. 337 - 350
[4] Tetrahedron Letters, 1992, vol. 33, # 1, p. 105 - 108
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