【摘 要】
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Through B3LYP/6-31G** calculations, the 1, 4-pyrone effects on O-H bond dissociation energies (BDEs) of catechols in rings A or B of flavonoids were investigate
【出 处】
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Chinese Chemical Letters
论文部分内容阅读
Through B3LYP/6-31G** calculations, the 1, 4-pyrone effects on O-H bond dissociation energies (BDEs) of catechols in rings A or B of flavonoids were investigated. For the catechol in ring A, although 1, 4-pyrone enlarged the conjugation system, its electron-withdrawing property increased the O-H BDE ~ 3 4.184 kJ/mol compared with that of catechol. However, for the catechol in ring B, 1, 4-pyrone was poorly conjugated with the moiety, and therefore, had little effect on the O-H BDE.
Through B3LYP / 6-31G ** calculations, the 1, 4-pyrone effects on OH bond dissociation energies (BDEs) of catechols in rings A or B of flavonoids were investigated. For the catechol in ring A, although 1, 4-pyrone enlarged the conjugation system, its electron-withdrawing property increased the OH BDE ~ 3 4.184 kJ / mol compared with that of catechol. However, for the catechol in ring B, 1, 4-pyrone was poorly conjugated with the moiety, and therefore, had little effect on the OH BDE.
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