Swim did a qualitative test of an oxidation protocol for phenylalanine - 500mg capsule of phenylalanine was placed in a test tube with about 100-150mg of the dichromate and about 15 ml of distilled water. After getting the dichromate to fully dissolve, the first thing that happened was a sweet smell which resembled rose oil, and then as the reaction proceded it finally smelt like marzipan.
When this story was related to me i asked myself what would happen when oxidising it. Is there a point where the reaction would tend to stop at, that is to say, is it possible that the reaction with bleach or permanganate or whatever will tend to result in some decomposed material and mostly benzaldehyde? Not exactly the most cost effective source for it, granted, but if economy is not paramount, still useful.
After watching the reaction SWIM felt that oxidising the phenylalanine would require a very mild oxidiser, i thought perhaps even 6% peroxide would be strong enough. It really doesn't have to be very strongly oxidised at all.
Otherwise, this bleach reaction should be added to the benzaldehyde synths imho, nutrasw**t is a cheap source of phenylalanine and a simple pH separation would yield the material. There is something like 150mg of phenylalanine in an average banana. I believe it is possible to get in powder pure form too.
A further test with 6% H2O2 will be done. The almost rose smelling aldehyde that is formed almost certainly must be phenylacetaldehyde. A gentler oxidiser and a larger volume of water is probably what is needed, there was likely material that remained unreacted.
If the right molar ratio were used, and excess water, would that help increase the ratio of phenylacetaldehyde that is formed?