What is the difference between aliphatic and aromatic aldehydes

Rodriguez , M. The effect of nonvertical alignment on the performance of a falling-cylinder viscometer. Journal of Physics D: Applied Physics , 5 1 , An automatic high pressure viscometer. Journal of Physics E: Scientific Instruments , 4 3 , Wohlfarth , B. References for Pure Organic Liquids. Pair your accounts. Your Mendeley pairing has expired.

Please reconnect. This website uses cookies to improve your user experience. By continuing to use the site, you are accepting our use of cookies. This redistributes the effect of electron-withdrawing nature of oxygen in —CHO group which incorporate with the aromatic ring. Therefore, the aromatic ring makes the aldehyde group less electrophilic. In other words, these molecules have resonance stabilisation.

Aliphatic aldehydes are organic compounds that have no aromatic rings attached to the aldehyde group.

Moreover, these molecules do not have any aromatic ring attached to anywhere of the compound. Since there are no aromatic rings, these molecules have no resonance stabilization. Therefore, these molecules have highly electrophilic —CHO groups, thus, the reactivity of the molecule is very high.

Aliphatic aldehydes are organic compounds which have no aromatic rings attached to the aldehyde group. This is the main difference between aromatic and aliphatic aldehydes. Furthermore, aromatic aldehydes have resonance stabilization. Thus, the reactivity of these molecules is very less. How I think about it is via resonance structures. Here's an example of an aromatic aldehyde, as compared to an aliphatic aldehyde:.

As a result, it extends the delocalization of the pi electrons by redistributing the effects of the electron-withdrawing nature of oxygen in the carbonyl group to incorporate the aromatic ring. In fact, you could draw two more resonance structures showing the distribution of the electropositivity onto the other two aromatic carbons, each one meta to the previous. Thus, you can see that the presence of the aromatic ring makes the carbonyl carbon less electrophilic through the redistribution of the electropositivity throughout the aromatic ring instead of just on the carbonyl carbon.

If you think about it like glasses of water, then that means the widespread distribution decreases the amount of positive charge water on each electropositive carbon in each glass. Or, you could say that the aliphatic aldehyde "puts its water in only one glass". Therefore, the greater electrophilicity of the aliphatic aldehyde's carbonyl carbon makes it more reactive.