Cyclohexane → HCID 69266098, compound

Participants

Reaction Conditions

Reaction Steps

A solution of sec-BuLi in cyclohexane (1.4 M, 2.65 mL, 3.71 mmol, 1.40 equiv) was added to a solution of tertramethylethylenediamine (0.880 mL, 5.83 mmol, 2.20 equiv) and tert-butyl(2S,4S)-4-{[tert-butyl(dimethyl)silyl]oxy}-2-phenylpyrrolidine-1-carboxylate (5-1, 1.00 g, 2.65 mmol, 1 equiv) in THF (150 mL) at −78° C. The resulting bright yellow mixture was stirred for 1 hour, then methyl trifluoromethanesulfonate (1.20 mL, 10.6 mmol, 4.00 equiv) was added. The mixture was warmed to 0° C. and stirred for 30 minutes, then partitioned between saturated sodium chloride solution (100 mL) and ethyl acetate (2×75 mL). The combined organic layers were dried over sodium sulfate and concentrated. The residue was purified by flash column chromatography (hexanes, grading to 50% ethyl acetate in hexanes) to provide tert-butyl(2S,4S)-4-{[tert-butyl(dimethyl)silyl]oxy}-2-methyl-2-phenylpyrrolidine-1-carboxylate (21-1) as a colorless oil. 1H NMR (500 MHz, CDCl3) δ 7.38-7.18 (m, 5H), 4.39 (m, 1), 3.92 (dd, 1H, J=10.8, 5.1 Hz), 3.65 (br d, 1H, J=10.8 Hz), 2.28 (dd, 1H, J=13.0, 4.5 Hz), 2.13 (br d, 1H, J=12.8 Hz), 1.92 (s, 3H), 1.12 (s, 9H), 0.91 (s, 9H), 0.03 (s, 3H), 0.02 (s, 3H). LRMS m/z (M+H-Boc) 292.2 found, 292.2 required.

Provenance & Evidence