4-Hydroxybenzaldehyde → (5E)-5-[(4-Hydroxyphenyl)methylidene]-1,3-thiazolidine-2,4-dione

Participants

Reaction Steps

A mixture of 4-hydroxy benzaldehyde, 36 (3 g, 24.6 mmol), 2,4-thiazolidinedione, 37 (2.9 g, 24.8 mmol), piperidine (2.5 mL) and methanol (100 mL) was refluxed for 18 h. The reaction mixture was poured into water and acidified with acetic acid to give 38, which was recrystallised from methanol. Yield 4.7 g (86%); mp 296-298° C.; MS (FAB) 222 (M++1); IR (KBr) 3404, 3123, 1723, 1678; 1H NMR (200 MHz, DMSO-d6) δ 7.70 (s, 1H), 7.46 (d, J=8.6 Hz, 2H), 6.93 (d, J=8.6 Hz, 2H).

Provenance & Evidence