tert-Butyldimethylsilyl Trifluoromethanesulfonate

Used Chemicals

• tert-Butyldimethylsilyl Triflate (=TBSOTf) [T1525]
• 2,6-Lutidine [L0067]
• α,α-Diphenyl-D-prolinol [D2365]
• Dichloromethane

Procedure

TBSOTf (1.36 mL, 5.92 mmol, 3.0 eq.) was added to a solution of α,α-diphenyl-D-prolinol (500 mg, 1.97 mmol) and 2,6-lutidine (1.4 mL, 11.8 mmol, 6.0 eq.) in dichloromethane (10 mL) at 0 °C. The mixture was stirred at r.t. for 20 hours and quenched with water (15 mL). The aqueous layer was extracted with dichloromethane (15 mL x 3) and the organic layer was washed with sat. NaHCO₃ aq. (15 mL) and brine (15 mL), dried over sodium sulfate and filtered. The solvent was removed under reduced pressure and the residue was purified by column chromatography (on silica gel, ethyl acetate:hexane = 1:4 - 1:1) to give 1 as a pale yellow syrup (410 mg, 57% yield).

Experimenter’s Comments

The reaction mixture was monitored by UPLC.

Analytical Data

Compound 1

¹H NMR (400 MHz, CDCl₃); δ 7.53-7.50 (m, 2H), 7.37-7.35 (m, 2H), 7.31-7.23 (m, 6H), 4.01 (t, J = 7.2 Hz,1H), 2.84-2.79 (m, 1H), 2.72-2.66 (m, 1H), 1.75 (brs, 1H), 1.62-1.48 (m, 3H), 1.28-1.16 (m, 1H), 0.95 (s, 9H), -0.21 (s, 3H), -0.47 (s, 3H).

Lead Reference

• Enantioselective Construction of Spirooxindole-Fused Cyclopentanes
• V. Dočekal, A. Vopálenská, P. Měrka, K. Konečná, O. Jand’ourek, M. Pour, I. Císařová, J. Veselý, J. Org. Chem. 2021, 86, 18, 12623.

References

• 1)Studies with Trialkylsilyltriflates: New Syntheses and Applications
  • E.J. Corey, H. Cho, C. Rucker, D. H. Hua, Tetrahedron Lett. 1981, 22, 3455.
• 2)Protection for the Hydroxyl Group, Including 1,2- and 1,3-Diols
  • P. G. M. Wuts, in Greene’s Protective Groups in Organic Synthesis, 5th ed., ed. by P. G. M. Wuts, John Wiley & Sons, Inc., Hoboken, New Jersey, 2014, Chap. 2, 17.

References

• C–C Coupling of Acyclic Nitronates with Silyl Ketene Acetals under Silyl Triflate Catalysis: Reactivity Umpolung of Aliphatic Nitro Compounds
• V. O. Smirnov, Y. A. Khomutova, V. A. Tartakovsky, S. L. Ioffe, Eur. J. Org. Chem. 2012, 3377.

References

• Studies with trialkylsilyltriflates: new syntheses and applications
• E. J. Corey, H. Cho, C. Rucker, D. H. Hua, Tetrahedron Lett. 1981, 22, 3455.