Hydrochloric Acid → 4,5-DIIODO-BENZENE-1,2-DIAMINE

Participants

Reaction Steps

Following a literature procedure, a sample of 1 (17.42 g, 41.5 mmol) and a magnetic stirring bar were added to a 500 mL conical flask fitted with a jacketed condenser. EtOH (95%, 150 mL) and conc. aqueous HCl (68.6 mL, 0.83 mol) were added, and the mixture was stirred and heated to boiling. Fe (18.59 g, 0.332 mol) was added in portions, resulting in foaming of the mixture and accelerated refluxing of the EtOH, which would subside within a few minutes of each addition. The reaction was heated for an additional 45 min beyond the final addition of Fe. A hot solution of EDTA (156 g, 0.411 mol, in 300 mL H2O) was added to the reaction mixture, and KOH pellets were added until the solution was alkaline to pH paper. The hot mixture was extracted twice with ethyl acetate and the extracts were combined, washed with water, followed by brine, dried over Na2SO4, filtered and concentrated to dryness. The residue was recrystallized (EtOH/water), giving tan needles (9.92 g, 66%): mp 135-136° C.; 1H NMR (d8-THF) δ 4.21 (brs, 4H), 7.03 (s, 2H); 13C NMR (d8-THF) δ 91.1, 124.5, 137.6; Anal. Calcd for C6H6I2N2: C, 20.02; H, 1.68; N, 7.78. Found: C, 20.19; H, 1.59, 7.71.

Provenance & Evidence