Thienyl Chalcone 유도체의 가수분해 반응메카니즘과 그 반응속도론적 연구

The Kinetics and Mechanism of the Hydrolysis to Thienyl Chalcone Derivatives

The hydrolysis reaction kinetics of 2-thienyl chalcone derivatives 〔Ⅱ〕~〔Ⅴ〕was investigated by ultraviolet spectrophotometery in 20% dioxane-H₂O at 25℃ and the structure of these compounds were ascertained by means of ultraviolet, infrared and NMR spectra. The rate equations which were applied over a wide pH range(pH 1.0~13.0) were obtained. The substituent effects on 2-thienyl chalcone derivatives[Ⅱ]~[Ⅴ] were studied, and the hydrolysis were facilitated by electron attracting groups. On the basis of the rate equation, substitutent effect and final product, the plausible hydrolysis reaction mechanism was proposed : At pH 1.0~9.0, not relevant to the hydrogen ion concentration, neutral H₂O molecule competitvely attacked on the double bone. By contraries, above pH 9.0, it was proportional to concentration of hydroxide ion.