N'-butylethane-1,2-diamine

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of N-butylethylenediamine (4.78 ml, 34.4 mmol) in isopropanol (60 ml) at 0° C. under a nitrogen atmosphere was added diethyloxalate (4.67 ml, 34.4 mmol). The reaction was allowed to warm to rt and heated to reflux for 6 h. The reaction was concentrated in vacuo and purified via flash chromatography (silica) to yield 1-butylpiperazine-2,3-dione (44%). heated to reflux for 6 h The reaction was concentrated in vacuo purified via flash chromatography (silica)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of N-butylethylenediamine (4.78 ml, 34.4 mmol) in isopropanol (60 ml) at 0° C. under a nitrogen atmosphere was added diethyloxalate (4.67 ml, 34.4 mmol). The reaction was allowed to warm to rt and heated to reflux for 6 h. The reaction was concentrated in vacuo and purified via flash chromatography (silica) to yield 1-butylpiperazine-2,3-dione (44%). heated to reflux for 6 h The reaction was concentrated in vacuo purified via flash chromatography (silica)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Reaction of N-butylethylenediamine (10.7 g, 0.092 mol) with cyanogen bromide (9.76 g, 0.092 mol) as described in the preparation of intermediate 6 gave 11.77 g (57% yield) of the title compound as white crystals (ether-hexane). 1HNMR 400 MHz (CDCl3) δ (ppm): 0.96 (3H, t, J=7.2 Hz, CH3), 1.41 (2H, m, CH2), 1.60 (2H, m, CH2), 3.52 (2H, t, J=7.3 Hz, CH2), 3.64-3.74 (4H, m, 2×CH2), 7.58 and 7.7 (broad s, NH). MS (ESI+) m/e 142 [M+H+].

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of N-butylethylenediamine (4.78 ml, 34.4 mmol) in isopropanol (60 ml) at 0° C. under a nitrogen atmosphere was added diethyloxalate (4.67 ml, 34.4 mmol). The reaction was allowed to warm to rt and heated to reflux for 6 h. The reaction was concentrated in vacuo and purified via flash chromatography (silica) to yield 1-butylpiperazine-2,3-dione (44%). heated to reflux for 6 h The reaction was concentrated in vacuo purified via flash chromatography (silica)