Ethyl Acetate → Benzyl 3-bromopropylcarbamate

Beteiligte Stoffe

Reaktionsschritte

3-Bromopropylamine hydrobromide (5.0 g, 22.8 mmol) was dissolved in an aqueous NaOH solution (15 wt %, 80 ml) and cooled to 0° C. under nitrogen before benzyl chloroformate was added dropwise. The reaction was left to stir overnight then ethyl acetate (100 ml) was added and the phases were separated. The organic phase was further washed with a HCl solution (2 M, 100 ml), a NaOH solution (2 M, 100 ml), brine (100 ml), dried over Na2SO4, and evaporated to yield 12 as a clear oil (6.22 g, 22.8 mmol, 100%). Rf=0.31 (8:2 Hexane/Ethyl acetate); 1H NMR (300 MHz, CDCl3) δ=7.40-7.33 (m, 5H, ArCH), 5.11 (s, 2H, CH2Ph), 4.94 (bs, 1H, NHCbz), 3.45 (t, 3J(H,H)=6.4 Hz, 2H, CH2Br), 3.36 (q, 3J(H,H)=6.4 Hz, 2H, CH2NHCbz), 2.08 (q, 3J(H,H)=6.4 Hz, 2H, CH2CH2CH2); 13C NMR (75 MHz, CDCl3) δ=156.4 (CO), 136.4 (ArCCH2), 128.5 (ArCH), 128.2 (ArCH), 127.0 (ArCH), 66.8 (CH2Ph), 39.4 (CH2NHCbz), 32.4 (CH2CH2CH2), 30.6 (CH2Br); HRMS (ESI+): m/z calculated for C11H14BrNO2Na [M+Na]+: 294.0106, found 294.0099.

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