Synthesis
The general procedure for the synthesis of 3-bromomethyl-3-methyl-1-oxetane from 3-methyl-3-hydroxymethyl oxetane was as follows: 10 ml (0.1 mol) of 3-methyl-3-hydroxymethyl oxetane and 36.58 g (0.11 mol) of carbon tetrabromide were dissolved in 100 ml of dichloromethane. The reaction mixture was cooled to 0 °C under nitrogen protection and 31.56 g (0.12 mol) of triphenylphosphine was slowly added. Subsequently, the reaction mixture was warmed to room temperature and stirred continuously for 20 minutes. Upon completion of the reaction, the solvent was removed by distillation under reduced pressure. To the residue, 100 mL of ethyl acetate was added and filtered using diatomaceous earth to remove insoluble impurities. The filtrate was concentrated under reduced pressure and recrystallized by adding hexane. The mixture was again filtered using diatomaceous earth and the filtrate was concentrated under reduced pressure to give the crude product. Finally, 16 g of 3-bromomethyl-3-methyl-1-oxetane was obtained by fractional purification in 95% yield. The nuclear magnetic resonance hydrogen spectrum (1H NMR, CDCl3, 300 MHz) data of the product were as follows: δ 4.46-4.38 (double peak, 4H), 3.65 (single peak, 2H), 1.44 (single peak, 3H).
References
[1] Journal of Organic Chemistry, 1998, vol. 63, # 11, p. 3631 - 3646
[2] Patent: EP1927592, 2008, A1. Location in patent: Page/Page column 11
[3] Journal of the Chemical Society, Dalton Transactions: Inorganic Chemistry (1972-1999), 1981, p. 1406 - 1414
[4] Acta Chemica Scandinavica, 1991, vol. 45, # 1, p. 82 - 91
[5] Journal of Organic Chemistry, 1998, vol. 63, # 11, p. 3631 - 3646
