Thiophene-2-carbohydrazide → 4-cyclopropyl-5-thien-2-yl-4H-1,2,4-triazole-3-thiol

Participants

Reaction Conditions

Reaction Steps

To a slurry of thiophene-2-carboxylic acid hydrazide (866 mg, 6.09 mmol) in iPrOH (25 ml) was added isothiocyanato-cyclopropane (602 mg, 6.08 mmol). The mixture was stirred at 70° C. for 72 h and then cooled to room temperature. The white precipitate was filtered off and suspended in a MeOH:H2O (9:1, 40 ml) together with aq. NaOH (2%, 5 ml). The reaction mixture was stirred at 70° C. overnight and then cooled to room temperature. The pH was adjusted to around 4 with aq. HCl (1N). The formed white precipitate was filtered off, washed with water and dried under vacuum (829 mg, 61%). 1H NMR (CD3OD), δ (ppm): 7.67 (dd, 1H), 7.63 (dd, 1H), 7.17 (dd, 1H), 3.15 (m, 1H), 1.14 (m, 2H), 0.86 (m, 2H).

Provenance & Evidence