The phenylthiosemicarbazide derivative
3 was prepared from 2-isopropyl-5-methylphenoxyacyl hydrazide (
1) and phenyl isothiocyanate (
2) [
1,
2]. A mixture of
1 (0.5 g, 2.25 mmol) and
2 (0.30 g, 2.25 mmol) in aqueous hydrochloric acid (15 mL, 50%) was heated under reflux for 3 hours. The reaction mixture was cooled to room temperature and the precipitate thus formed was filtered, washed with copious amount of water and recristallized from ethanol to give
3 as white cristals. (0.71 g, 88%).
M.p. 156-158 oC (EtOH, uncorrected).
UV λmax (nm; Acetone)/e (dm3.mol-1.cm-1) 274/17090, 355/4200.
IR νmax (cm-1; KBr Disk) 3292, 3234 (NH), 2657 (SH), 1674 (C=O), 1553 (NH bending).
1H-NMR (400 MHz; CDCl3; Me4Si) δH 0.95 (6H, d, 2CH3), 2.03 (3H, s CH3), 3.17 (1H, m, CH), 4.36 (2H, S, CH2O), 6.40 (1H, s), 6.51 1H, d, J = 7.63 Hz), 6.83 (1H, d, J =7.73 Hz), 6.88 (1H, d, J =7.35 Hz), 7.05 (2H, t, J =7.85 Hz), 7.24 (2H, d, J =7.5 Hz).
13C-NMR (δC) 21.44, 23.24, 26.50, 67.15 (CH2O), 112.5, 122.63, 124.0, 125.47, 126.3, 128.8,134.38, 136.7, 138.8154.58.
Elemental Analysis: Calculated for C19H23N3O2S ( 357.22): C 63.88, H 6.44, N 11.77; found : C 63.67, H 6.56 , N 11.62.
