2-Amino-6-nitrobenzothiazole → 2,6-Benzothiazolediamine

Participants

Reaction Steps

A mixture of 6-nitro-benzothiazol-2-ylamine (1.0 g, 5.12 mmol) and SnCl2 (4.86 g, 25.6 mmol) in 15 mL ethanol (denatured) was heated at reflux for 1 hour. The mixture was concentrated and partitioned between 100 mL CH2Cl2 and 50 mL 1.0 N NaOH. The organic layer was separated and the aqueous layer was extracted with 2×100 mL of CH2Cl2. The combined organic fractions were dried over MgSO4, filtered and evaporated to give a yellow solid. This was washed with a 1:1 mixture of Et2O and hexanes. Yield: 50%; 1H-NMR (acetone-d6): δ 7.14 (d, 1H, J=8.8 Hz); 6.92 (d, 1H, J=1.9 Hz); 6.62 (dd, 1H, J=1.9, 8.5 Hz).

Provenance & Evidence