Trimethylsilyl isocyanate → 4-(2-Tert-butoxycarbonylaminoethyl)piperidine-1-carboxamide

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

4-(2-tert-Butoxycarbonylaminoethyl)piperidine (500 mg, 2.19 mmoles) was dissolved in anhydrous dichloromethane (10 mL) and trimethylsilylisocyanate (2.96 mL, 21.9 mmoles) was added. The mixture was stirred under argon at 25° C. for 3.25 h. The mixture was diluted with dichloromethane and washed with saturated aqueous sodium bicarbonate. The organic layer was dried (MgSO4), filtered, evaporated to dryness and chromatographed on a silica gel column (15×5 cm) using 5% (10% conc. ammonium hydroxide in methanol)-dichloromethane as the eluant to give 4-(2-tert-butoxycarbonylaminoethyl)piperidine-1-carboxamide (308.2 mg, 52%): FABMS: m/z 272.0 (MH+); HRFABMS: m/z 272.1965 (MH+). Calcd. for C13H26O3N3: m/z 272.1974; δH (CDCl3) 1.20 (2H, m, CH2), 1.47 (9H, s, —COOC(CH3)3), 1.45–1.55 (3H, m, CH/CH2), 1.75 (2H, m, CH2), 2.82 (2H, m, CH2), 3.19 (2H, m, CH2), 3.96 (2H, m, CH2), 4.64 (2H, m, CH2) and 4.70 ppm (1H, bm, NH); δC (CDCl3) CH3: 28.5, 28.5, 28.5; CH2: 31.8, 31.8, 36.7, 38.0, 44.5, 44.5; CH: 33.4; C: 79.2, 156.7, 158.1.

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