3.15 Ketones and Imines

Ketones are similar to aldehydes, but instead of a -CHO group, they have a C-C(=O)-C group. Acetone CH₃COCH₃ and methyl ethyl ketone CH₃CH₂COCH₃ are a common solvents. Methyl amyl ketone CH₃CO(CH₂)₄CH₃ is a ketone that smells like rotten bananas and actually occurs naturally in potato chips. More complex ketones turn up in various flavors and aromas, such as the rose ketones, present in tiny amounts in rose oil, and adding the tiniest nuances to make the scent more realistic:

α-damascone

β-damascone

α-ionone

β-ionone

Imines are compounds with a C=N bond. They can be divided into aldimines with a -CH=N- group and ketimines with a -C(=N-)- group, by analogy with aldehydes and ketones. Acetone imine is an example of a ketimine: CH₃C(=NH)CH₃.

(Be careful not to confuse ketimines with ketamine, as those are very different things.)

Acetone imine is an example of a primary imine, one where the atoms bonded to the nitrogen are the carbon and a hydrogen. A secondary imine replaces the hydrogen with another organic group; we will see an example in a later section.

Next Lesson | Table of Contents | Main