2 (100 g, 0.47 mol) was mixed with 2-diethylaminoethyl chloride hydrochloride (300 g, 1.74 mol), KOH (225 g, 4.01 mol), water (320 mL), and toluene (1.5 L), and the reaction was carried out at reflux for 24 hours. After completion of the reaction, the emulsion was cooled to room temperature and the organic layer was separated. The organic layer was washed with 3 mol/L aqueous KOH (500 mL) and subsequently concentrated to dryness under vacuum. The residue was dissolved in anhydrous ethanol (420 g) and the pH was adjusted to 3.0 by passing gaseous HCl. The orange product was recrystallized by ethanol, and after filtration and drying, 200 g of tilolone hydrochloride (Compound 1) was obtained in 93% yield. The melting point of the product was 231-233°C (literature value 235-236°C [22]).IR (KBr) spectrum showed characteristic absorption peaks: 2943.3, 2596.5 (CH), 1708.9 (C=O) cm?1. ESI-MS (m/z): 411.0 [M+H]? , molecular formula C??H??N?O? (molecular weight 410.3).1H-NMR (400 MHz, D?O) chemical shift δ (ppm): 7.12 (d, J=6.5Hz, 2H), 6.99 (dd, J=6.5,1.6Hz, 2H), 6.89 (d, J=1.6Hz, 2H), 4.39 (t, J=3.6Hz , 4H), 3.68 (t, J=3.6Hz, 4H), 3.42 (q, J=5.6Hz, 8H), 1.44 (t, J=5.8Hz, 12H).
