Diisopropylethylamine → HCID 58374102, compound

Participants

Reaction Steps

To a mixture of (S)-ethyl 1-((S)-2-(4-cyanophenyl)-2-hydroxyethyl)piperidine-3-carboxylate (17.0 g, 56.2 mmol) and DIPEA (17.68 ml, 101 mmol) in CH2Cl2 (187 mL) was added tert-butyldimethylsilyl trifluoromethanesulfonate (16 ml, 69.6 mmol) slowly. The reaction was monitored with HPLC. The reaction completed in 2 hours. The reaction mixture (a light brown solution) was quenched with water, the aqueous layer was extracted with DCM. The organic phase was combined and dried with Na2SO4. After concentration, the crude material was further purified on a silica gel cartridge (330 g silica, 10-30% EtOAc/hexanes gradient) to afford a purified product (S)-ethyl 1-((S)-2-(tert-butyldimethylsilyloxy)-2-(4-cyanophenyl)ethyl)piperidine-3-carboxylate (22.25 g, 53.4 mmol, 95% yield). 1H NMR (400 MHz, CDCl3) δ ppm 7.61 (2H, d), 7.45 (2H, d), 4.79 (1H, m), 4.15 (2H, m), 2.88 (1H, m), 2.75 (1H, m), 2.60 (1H, dd), 2.48 (1H, m), 2.40 (1H, dd), 2.33 (1H, tt), 2.12 (1H, tt), 1.90 (1H, m), 1.68 (1H, dt), 1.52 (1H, m), 1.48 (1H, m), 1.27 (3H, t), 0.89 (9H, s), 0.08 (3H, s), −0.07 (3H, s).

Provenance & Evidence