A mild oxidation of the reaction mixture, using something like MnO
2, K
2CrO
3 or similar (
UTFSE for ""aldehyde AND oxidation""
), will not affect the MDP2P but will oxidize the aldehyde to MD-Phenylpropionic acid, which in turn can be easily removed by a simple bicarbonate wash.
![](https://www.thevespiary.org/rhodium/Rhodium/hive/hiveboard/picproxie_docs/000438200-file_vx7q.gif)
The amine gotten from reductive amination of the aldehyde ("MDP3P") would be 3-(3,4-Methylenedioxyphenyl)-propyl-methyl-amine, and while it probably isn't very psychoactive at the dosages involved, it may have toxic effects, so to do your fellow human beings a favor, clean your conscience - clean your ketone.
Distillation of the freebase gotten after an acid/base extraction of the Al/Hg reaction mixture, followed by recrystallization of the precipitated HCl salt will probably help removing a majority of the above impurity, but it does not beat the oxidation + base wash suggested above to remove it completely.
(09-09-04):
The boiling point of MDP3P (MD-Phenylpropionaldehyde) is 104-106°C at 0.3mmHg [Ref: Synthesis (2), 151-153 (1980) and Tetrahedron 42(20), 5515-5522 (1986)] while that of MDP2P (MD-Phenylacetone) is 100-110°C at 0.2 mmHg [Ref: J. Anal. Tox. 6, 71-75 (1982)]. As the substances essentially shares the same boiling range, there is no use even trying to separate them through distillation as they will always distill as a single fraction.