Samarium(II) Iodide (ca. 0.1mol/L in Tetrahydrofuran)

Typical procedure: Nitrone 1 (50 mg) is co-evaporated with toluene (1 mL x 3) at 35 °C then is deoxygenated. To the solution of 1 in dry THF (0.5 mL), a 0.1 mol/L THF solution of SmI₂ (2.0 mL) is added at -60 °C under argon. After disappearance of the typical blue color, cyclohexanecarboxaldehyde (25 micro L) is added and the temperature is raised to room temperature over 5 h. A saturated aqueous solution of Na₂S₂O₃ (2 mL), a saturated aqueous solution of NaHCO₃ (2 mL) and EtOAc (2 mL) are added. The aqueous phase is extracted with EtOAc (20 mL x 2), and the combined extracts are dried over MgSO₄. Concentration gives a crude oil. Purification by silica gel chromatography (eluent: pentane/EtOAc=6/1 to 0/1 then EtOAc/MeOH=8/1) gives 3 (39 mg, 77%) as a pale yellow oil.