Problems with the benzoic acid condensation reaction

Let’s go through them one by one. Disproportionation reaction: The Cannizzaro reaction is a type of self-reaction, which can be divided into self-disproportionation (involving 2 molecules of an aldehyde) and cross-disproportionation (involving different aldehydes). The condition for this reaction is the use of NaOH (concentrated base), and the reactants must be aldehydes that do not contain alpha hydrogens. Aldol condensation, on the other hand, is a condensation reaction that occurs with aldehydes containing alpha hydrogens, either under the catalysis of acid or weak base. It can also be divided into three categories: self-aldol condensation (involving 2 molecules of the same aldehyde) and cross-aldol condensation (involving different aldehydes). The reaction takes place in NaOH (weak) solution or ethanol solution. A typical example of such a reaction is the Claisen-Schmidt reaction. Since the reactants can be different aldehydes or the same aldehyde, the reaction products are not unique. Moreover, in the final product, the large group containing a C=O bond is in a trans configuration relative to another large group. This post was last edited by zhangyong6404 on 2009-3-16 02:28

As a supplementary note: The products obtained in such aldol condensation reactions are all unsaturated, as the β-hydroxy group readily undergoes dehydration. In some cases, dehydration occurs during the reaction itself, while in other cases it takes place after the reaction under acidic or basic conditions. Oriented aldol condensation is the third type of aldol reaction; it is an asymmetric reaction. Therefore, under acidic or basic conditions, different methylene groups attached to the carbonyl groups yield different carbanions. Such reactions are influenced by the solvent used and by steric factors, and they are also governed by reaction kinetics. Finally, regarding benzaldehyde condensation: simply put, the reactants must be aromatic aldehydes, and the reaction takes place in the presence of CN- ions. You can refer to the previous explanations on aldol condensation for the reaction mechanism. Lastly, for such organic chemistry questions… it’s not appropriate to ask them on a chemical forum like Haichuan. You might want to post your questions on the China Chemical and Chemical Engineering Forum: http://www.ccebbs.com/. This post was last edited by zhangyong6404 on 2009-3-16 02:38

I think a forum section on organic chemistry could be created. This will not only help the forum to grow and develop but also attract more professionals in the field of chemistry to it.

It is indeed necessary to establish an organic synthesis section

It also gives me a chance to put my skills to use. I wait every day for someone to ask questions about organic or chemically treated products; my hair has almost turned white from waiting…