Presumptive tests

[Fertile]

Has anyone come across a presumptive test for (alkylsulfanyl)benzenehioethers e.g. 4MTA, 2-C-T-7 and so forth?

I mean, thioethers are quite reactive. hydrogen peroxide will oxidise them to (methanesulfinyl)benzene so a presumptive test for one of those is just as good.

At the moment I'm looking at oxidants like I2 which will oxidise and form HI. Not much but enough so a narrow pH test might spot it. But any and all ideas gladly accepted. their has been another flood of 4MTA deaths in Europe and so it's important to have an appropriate test.

 

[Fertile]

I must have spent about 40 hours looking for a test for arylalkyl thioethers with not much to show.

I have learnt that they are easily oxidised to the sulfone and the sulfoxide. Some reagents quickly form sulfone but only slowly form sulfoxide, some just go to sulfoxide. No presumptive test for sulfone, no presumptive test for sulfoxide.

I also found that they react with things like CH3I to form sulfonium ions thus:
CH3–S–CH3 + CH3–I → (CH3)3S+I−

Now that should alter solubility, but it's taking things an awfully long way from that which is known.

I DID find a really simple (2 well) test that would detect if an alkaloid had a:

a) primary amine
b) secondary amine
c) tertiary amine

So along with the Chen-Kao reagent would detect cathinones. I found a more modern test that uses Cu(II)-neocuproine and gives different colour changes depending on ring-substitution and length of alkyl chain.

Lastly, I've remembered a REALLY important detail of benzodiazepine chemistry. In acidic conditions (pH lower than 4), the imine is hydrolized and so an amine and a benzophenone are both available to test:

test hosted at ImgBB

Image test hosted in ImgBB

ibb.co

I think the amine will react with nitrous acid so primary amines will form alkanes, secondary amines nitroso compounds.

So slowly I am chipping away at the problem.

The synthetic cannabinoids are the hardest to test since there are 5 classes. I have 2 tests already so I can find 80% of them.