醛酮类有机物中羰基氧原子的杂化状态

Hybrid State of Carbonyl Oxygen Atom in Aldehyde and Ketone

有机化学教科书及有关专著对羰基中氧原子的杂化状态,存在着不一致的观点。羰基中氧原子的杂化状态,在一定程度上会影响羰基的极性强弱,进而对羰基的化学性质产生细微的影响,特别是对其亲电加成反应活性的潜在影响。借助理论计算,发现醛、酮分子中羰基氧与碳成键时既不是彻底的sp2杂化状态,也不是非杂化直接成键,而是采用了一种介于sp^2与非杂化之间的一种成键状态。

There are controversial viewpoints on the hybrid state of carbonyl oxygen atom in the organic chemistry textbooks and some monographs. The hybridization state of O atoms in the carbonyl group affects on the polarity of carbonyl groups in a certain degree. Consequently, it will slightly affect on the chemical properties of the carbonyl group, especially on its electrophilie addition reaction activity. By means of theoretical calculation, it is found that the carbonyl oxygen of aldehyde or ketone molecules is neither in complete sp^2 nor in non-hybrid state when it bonds with carbonyl carbon, but in a status between sp^2 and non-hybrid.