酚钠和二氧化碳在加压下于125－150 ºC反应，生成邻羟基苯甲酸，同时有少量对羟基苯甲酸生成：

反应产物与酚盐的种类及反应温度有关，一般来讲，使用钠盐及在较低的温度下反应主要得到邻位产物，而用钾盐及在较高温度下反应则主要得对位产物：

邻位异构体在钾盐及较高温度下加热也能转变为对位异构体：

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反应机理

Kolbe-Schmitt Reaction

A base-promoted carboxylation of phenols that allows the synthesis of salicylic acid derivatives.

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Mechanism of the Kolbe-Schmitt Reaction

 

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参考文献

[1] H. Kolbe, Ann. 113, 125 (1860)
[2] R. Schmitt, J. Prakt. Chem. [2] 31, 397 (1885)
[3] H. Kolbe, J. Prakt. Chem. [2] 10, 89 (1874); 11, 24 (1875)
[4] R. Schmitt, Ber. 20, 2702 (1887)
[5] S. Marasse, Ger. pats. 73,279; 8,708
[6] S. E. Hunt et al., J. Chem. Soc. 1958, 3152
[7] H. Gilman et al., J. Org. Chem. 10, 4 (1945)
[8] D, Cameron et al., ibid. 15, 233 (1950)