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Where does the aldehyde group usually attach during the Reimer-Tiemann reaction?
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aldehyde
Alcohols may be oxidized to give aldehydes, ketones, and carboxylic acids. The oxidation of organic compounds generally increases the number of bonds from carbon to oxygen, and it may decrease the number of bonds to hydrogen.
In the Reimer-Tiemann reaction, the aldehyde group typically attaches to the ortho position of the phenol ring. While para-substitution can also occur, the ortho product is generally favored due to the reaction mechanism involving the formation of a dichlorocarbene intermediate that attacks the electron-rich aromatic ring.1