Hi!
When using this (https://www.thevespiary.org/rhodium/Rhodium/chemistry/p2p.sncl2.html)
(https://www.thevespiary.org/rhodium/Rhodium/chemistry/p2p.sncl2.html) method for the reduction of nitopropenes to ketones, it seems that the major by-product is the benzaldehyde. It shouldn't be much (app. 5%) when using the ethylacetate method, but with IPA the contamination rises to about 40%. This can be removed by distillation, but it would nice to have a slick way of removing it.
I had thought about suspending the oil (ketone and benzaldehyde after steam distillation) in dilute cold aq. NaOH and titrating with 1M KMnO4, untill a purple color persists. In a perfect world the benzaldehyde would be oxidized to benzoic acid, and this should dissolve in the basic medium. The ketone could then be isolated directly by the extraction with a proper NP.
The only thing that worries me about this scheme is the possible oxidative cleavage of the benzyl CH2 group in the ketone. I have not found any conclusive answer to when permanganate will cause oxidative cleavage at the benzyl carbon.
Anyone have some neat suggestions or comments?
Kind regards
Bandil