关键词: 紫外分光光度法, 取代基效应, 共轭体系, 查耳酮, 戊二烯酮 P

Substituent constants (a) of chalcone conjugated compounds [I; R = H, m-NO2, p-Br, p-Ph; X = H, Me, MeO, Cl, NO2] were determine and showed a linear relationship with lmax. A linear relationship was also observed between the log of rate constants and Hammett reaction constant s with g > 0.98.

Key words: SUBSTITUENT EFFECT, ULTRAVIOLET SPECTROPHOTOMETRY, CHALCONE, PENTADIENONE P