Synthesis
To a solution of (S)-diphenylprolinol (4.00 g, 15.8 mmol, 1.00 eq.) in dichloromethane (40 mL) was added imidazole (3.22 g, 47.4 mmol, 3.00 eq.) at 0 °C. Trimethylchlorosilane (5.00 mL, 39.5 mmol, 2.50 eq.) was added slowly and the reaction mixture was subsequently stirred at room temperature for 12 hours. Upon completion of the reaction, the reaction mixture was diluted by addition of methyl tert-butyl ether (MTBE, 100 mL) and filtered to remove insoluble material. The organic phase was washed sequentially with water (50 mL) and saturated aqueous sodium chloride solution (2 x 50 mL), dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure to give the colorless oily product (2S)-2-[diphenyl[(trimethylsilyl ester)oxy]methyl]-pyrrolidine (11, 5.00 g, 15.3 mmol, 97% yield). The product was characterized by 1H NMR (400 MHz, CDCl3), 13C NMR (101 MHz, CDCl3) and HR-MS (ESI), and the data were consistent with the expected structure.
References
[1] Journal of the American Chemical Society, 2014, vol. 136, # 52, p. 18140 - 18148
[2] Bioorganic and Medicinal Chemistry, 2017, vol. 25, # 18, p. 4996 - 5001
[3] Angewandte Chemie - International Edition, 2005, vol. 44, # 27, p. 4212 - 4215
[4] Patent: WO2010/144293, 2010, A1. Location in patent: Page/Page column 29
[5] Journal of Organic Chemistry, 2010, vol. 75, # 22, p. 7829 - 7841