Acetaldehyde ammonia trimer is a chemical compound described by the formula (CH3CHNH)3. The pure material is colourless but samples often appear light yellow or slightly beige due to the degradation by oxidation. It is hygroscopic, and can be found in a trihydrate form.
As implied by its name, it is a trimeric species formed from the reaction of acetaldehyde and ammonia:
- 3 CH3CHO + 3 NH3 → (CH3CHNH)3 + 3 H2O
Studies using NMR spectroscopy indicate that the three methyl groups are equatorial, thus the molecule has C3v point group symmetry.
The compound is related to hexamethylenetetramine, which is the condensation product of the condensation of ammonia and formaldehyde.