Hydrochloric Acid → 1-N-[2-(diethylamino)ethyl]-4-nitrobenzene-1,2-diamine

Participants

Reaction Conditions

Reaction Steps

N′-(2,4-Dinitro-phenyl)-N,N-diethyl-ethane-1,2-diamine 3a (0.63 g, 2.322 mmol) was dissolved in anhydrous EtOH (9 mL) in a 2 neck 100 mL argon purged flask. The reaction vessel was fitted with a condenser and dropping funnel and heated in an oil bath to 65° C. H2O (7.5 mL), EtOH (15 mL) and aqueous (NH4)2S (50 wt %, 1.064 g, 7.807 mmol) were charged to the dropping funnel and added to the hot reaction mixture dropwise over 30 minutes. The reaction was heated at 65-70° C. for 2 hours then cooled to room temperature overnight. Mixture was acidified by the addition of aqueous 1M HCl to adjust pH to 0-1. The reaction mixture was filtered to remove any insoluble material and the filtrate was concentrated under reduced pressure to remove EtOH. The resulting aqueous solution was basified by the addition of aqueous 2M ammonium hydroxide solution to adjust pH to 9-10. The aqueous solution was diluted with dichloromethane and transferred to a separatory funnel and the organic layer collected. The aqueous layer was further extracted with dichloromethane and the combined organic layers were washed with H2O, brine, and dried over magnesium sulphate, filtered and concentrated to afford a dark red oil. The product was purified using silica gel dry column chromatography with a solvent system of (5% 2M NH3 in methanol/95% dichloromethane) to afford an orange oil/solid 4a N1-(2-Diethylamino-ethyl)-4-nitro-benzene-1,2-diamine. Yield: 0.476 grams (84.5%). 1H NMR (DMSO) δ 0.96 (t, 6H, J=7.1), 2.52 (m, 4H), 2.62 (t, 2H, J=6.8), 3.24 (m, 2H), 5.09 (br s, 2H), 5.82 (br s, 1H), 6.49 (d, 1H, J=8.9), 7.42 (d, 1H, J=2.6), 7.53 (dd, 1H, J=8.9, 2.6); MS (ESI): 253 (MH+, 100%)

Provenance & Evidence