Reaction Steps
The reaction was carried out in the dark. A solution of 4-fluoro-3-nitrophenyl azide (0.91 g, 5.0 mmol, Sigma) in 10 ml dry ether was added dropwise with stirring to a solution of 3.2 ml of N-(3-aminopropyl)-N-methyl-1,3-propanediamine (10 mmol, Aldrich) in 20 ml dry ether and the mixture was stirred for 30 min. The reaction was monitored using TLC (alumina, elution with methanol). The solvent was removed and the red oil was dissolved in 25 ml water, 25 ml 1.0M NaOH and then extracted into ethyl acetate (2×50 ml). The organic phase was dried over MgSO4 and the solvent then removed in vacuum. TLC: (I) alumina, eluted with methanol, Rf=0.43 (II) silica gel, elution with 1:9 AcOH/H2O, Rf between Rf=0.23 and Rf=0.55. 1H NMR (CDCl3 /TMS) δ: 1.45 (2H, broad s, NH), 1.64 (2H, m, CH2), 1.87 (2H, p, J=6.52 Hz, CH2), 2.25 (3H, s, CH3), 2.43 (2H, t, CH2), 2.47 (2H, t, J=6.46 Hz, CH2), 2.73 (2H, t, J=6.89 Hz, CH2), 3.37 (2H, m, J=6.61 Hz, CH2), 6.89 (1H, d, J=9.23 Hz, ArH), 7.10 (1H, dd, J=2.73, 9.20 Hz, ArH), 7.79 (1H, d, J=2.74 Hz, ArH), 8.47 (1H, m, NH). 13C NMR (CDCl3 /TMS) δ: 143.23 (Q), 131.24 (Q), 127.91 (CH), 127.16 (Q), 115.73 (CH), 115.44 (CH), 55.70 (CH2), 55.40 (CH2), 42.03 (CH2), 41.90 (CH3), 40.50 (CH2), 30.94 (CH2), 26.20 (CH2).
