Post 280053 (https://www.thevespiary.org/talk/index.php?topic=6870.msg28005300#msg28005300)
(Rhodium: "Why the Ritter Reaction Fails for Safrole", Chemistry Discourse)?In SOMM 3, I put that ritter reaction with safrole because I read the same article as you by the chair of the chem dept of UCLA. It doesn't work. In later eds of SOMM, I cite the reason why...Chem abtracts Vol 22 page 86 "Cleavage of the Methylenedioxy Group". Sulfuric acid rips apart the grouping. Just because a guy holds a chair in chem doesn't mean you should listen to him.
“The Ritter Reaction Using Safrole: An Encounter In Two Clandestine Labs”
Richard R. Laing and Brian Dawson, Health Protection Branch, Drug Analytical Service, Health Canada, 3155 Willingdon Green, Burnaby, B.C., V5G 4P2
In two recent MDA clandestine lab seizures, references were found relating to the Ritter reaction in which safrole, acetonitrile and concentrated sulphuric acid are reacted together at cold temperatures. In repeating the synthesis the desired intermediate N-acetyl MDA was not found at any stage of the reaction. The major reaction product, although seeming to relate to MDA was partially characterized using IR spectroscopy and mass spectrometry but require 1H and 13C NMR techniques for structure confirmation. The major product 3,4-dihydro 1,3-dimethyl-6,7-methylenedioxyisoquinoline does not appear to be the desired end product and has also recently been identified in two street samples from the Vancouver area.
“MDA From Safrole by the Ritter Reaction”
R. Kazlauskas and V. Murtaugh, Australian Government Analytical Laboratory, PO Box 385, Pymble, Sydney, NSW, Australia, 2071
The underground book by Uncle Fester, “Secrets of Methamphetamine Manufacture,” mentions use of the Ritter reaction to make MDA from safrole, by analogy to making amphetamine from allybenzene. But when the reaction is applied to safrole and acetonitrile, it gives only a low yield of the expected product, N-acetyl MDA. The major product appears to be an isoquinoline. It is suggested that clandestine lab chemists can use this compound as an indicator of the Ritter or related reactions.
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https://www.thevespiary.org/rhodium/Rhodium/chemistry/clic.html (https://www.thevespiary.org/rhodium/Rhodium/chemistry/clic.html)
<Post 404131 (missing)
(Fomalhaut: "Íåìíîãî òåîðèè...", Russian HyperLab)):Thanks I like to have a clear picture and you seem to know how to draw them.
Alas, i'm not that meticulous when it comes to explanation. As i noted above, it was Fomalhaut who both authored the idea and drew the rxns :)
Now, to summarize all of the above, after reading all those links and articles:
1. The 'classic' Ritter rxn is no good for safrol and all other methoxylated allylbenzenes.
2. This rxn DOES work to some extent at some milder conditions, as the clandestine market researches suggest.
It is not clear as to how good a yield one can obtain at best via this route.
Now, to give you guys smth to think of..... This reaction can bee run at lower temps and much reduced concentration of H2SO4, using AcOH as an adulterant:
Journal of Chromatographic Science, Vol. 33, 256-262 (1995) (https://www.thevespiary.org/rhodium/Rhodium/pdf/forensic/ritter-rxn.allylbenzene.pdf)
(https://www.thevespiary.org/rhodium/Rhodium/pdf/forensic/ritter-rxn.allylbenzene.pdf)