Hydrochloric Acid → 1-[4-(4-Oxo-2-thioxo-thiazolidin-5-ylidenemethyl)-phenyl]-piperidin-4-one

Participants

Reaction Steps

5-[4(1,4-Dioxa-8-aza-spiro[4.5]dec-8-yl)-benzylidene]-2-thioxothiazolidin-4-one (which was obtained in Example 33) (0.9 g, 2.5 mmol) was treated with concentrated hydrochloric acid (25 mL) at room temperature. After 15 hours ˜28% ammonium hydroxide (NH4OH) was added dropwise and the precipitate was collected by filtration, and dried over phosphorus pentoxide (P2O5) to give the title compound as a red solid (0.71 g, 89%); 1H NMR (300 MHz, DMSO-d6) δ 2.46 (t, J=6.1 Hz, 4 H), 3.79 (t, J=6.1 Hz, 4 H), 7.11 (d, J=9.0 Hz, 2 H), 7.48 (d, J=9.0 Hz, 2 H), 7.56 (s, 1 H); MS (ES) m/z: 316.9 (M−H)−; HRMS Calcd. C15H14N2O2S2(M+): 318.0497. Found: 31.8.0502.

Provenance & Evidence