Simple question:

Can a halogen exchange type reaction making use of a salt of which the target salt is highly soluable in a suitable polar solvent, and a cyanide, rather than an inorganic chloride, fluoride, bromide et?2 or a similar reaction3,5 (halex rxn) be performed using a cyanide, to displace a halogen or sulfonate ester from a benzylic halide (halogen being on the ring structure1, intent being to form the 4-cyano-substituted aldehyde, or finished substituted amine from a halo or OH-aldehyde/amine end product from nitroalkene synthesis via henry condensation)

Or do those reactions not work with cyanides....the CN ion is after all, a pseudohalogen4.

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Notes by Enkidu:

1. If the halogen is bonded to the ring, the moiety would be an aryl halide, not a benzyl halide.
2. The [Finkelstein] reaction works well for primary (except for neopentyl) halides, and exceptionally well for allyl, benzyl, and ?-carbonyl halides. Secondary substrates are marginal. Vinyl, aryl and tertiary alkyl halides are unreactive.
3. The reaction of an alkyl halide with a cyanide salt (producing a nitrile) is a nucleophilic substitution reaction (SN1 or SN2, depending on the R). R-Br + NaCN ---> R-CN + NaBr is a rudimentary rxn.
4. Pseudohalogen is a pharmacology term and not a synthesis term. Halogens obviously react quite differently than nitriles.
5. See the Sandmeyer reaction.

'if the halide salt is insoluable in......'

RCN-NOT halogens, but the cyanide is a psudohalogen, like azide or polyaluminium superatom clusters (I doubt that could be put on an aromatic ring though, and it may well not bind to 5HT2a as an agonist as such a  substitutent even if it could...the chemistry if possible would certainly not be easy going) hence the question.

I just wanted to know if this reaction is capable of being performed successfully, in a suitable solvent (regarding soluability) with the cyanide ion, taking into account its being a pseudohalogen. I don't know if CN will substitute in this way as would say, replacing bromine or chlorine with iodine or fluorine (fluorine requiring different conditions, often done with 18-crown-6)

This is not something Tsathoggua is immediately thinking of performing, once I report the responses the thread gains, as a good, dutifull, faithful demon-toad-god cultist should do but rather, for considering possible future synthetic targets.

 

Pseudohalogen referring to the similarity of electronic configuration, and in many cases, chemical behaviour, exhibited by cyanide and other moieties that exhibit a similar electronic configuration to the halogens, such as for instance, azide and the aforementioned, funky as hell aluminiumsuperclusters, groups of many aluminium atoms, bonded together that behave like a single atom in their chemistry and exhibit a similar electron-configuration arrangement again to the halogens, of course being much, much larger in their/its atomic radius.

http://en.wikipedia.org/wiki/Pseudohalogen

In this case, the idea would be to react 2,5-dimethoxy-4-chloro or para-bromoamphetamine or the aldehydes (possibly protected as the bisulfite adduct) with a cyanide salt, the cyanide salt being poorly soluable in a solvent of choice (which I haven't actually yet looked up, nor that of the halogenated aldehydes or amphetamine/phenethylamines, to give the para-cyano-amphetamine/phenethylamine.

The interest being, is that as is well known, certain 5HT2a agonists are powerfully psychedelic, such as LSD, DOB, DMT, psilocin, 2C-B, you name it, yet others are still just as potent as agonists at the receptor but fail to elicit psychedelic effects.

The reason I believe, is differential activity at 5HT2a, 2,5-dimethoxyamphetamine is actually a 5HT2a agonist, and yet while stimulating like an amphetamine, according to Shulgin is NOT a psychedelic, and the same goes for lisuride-potent 5HT2a agonist, non-psychedelic, DOCN is however, functionally selective at the other of the two intracellular second messenger signalling pathways involved. Some 5HT2a agonists activate the phospholipase-A2 cascade, and some preferentially activate PLC. I forget off the top of my head which does which, and have work to do now, so can't look it up in detail right now as to which is which, but both DOCN and 2,5-DMA are functionally selective (or to use the other terminology for the phenomena, they display protean agonism)

I am curious, about the nBOMe derivatives, n-(2-OH-benzyl) and n,-(2-halobenzyl) etc derivatives. An ultrapotent, functionally selective ligand with a very high affinity (and preferably efficacy) with functional selectivity would be a useful tool in scientific research.
Of course, the DOX bomamine would be of little use, and the idea relies on the cyano-phenethylamine displaying a similar functionally selective 5HT2a agonist effects.

Couldn't assay the selectivity for PLA2 over PLC myself of course, Tsathoggua doesn't have the equipment, but Tsathoggua would be interested in giving some to a researcher who could, maybe one day, and having it found out, if I could find someone interested in 5HT2a ligand research and willing to take a sample and find out if it could be made into a useful tool (providing it wasn't done in cells harvested in a way inflicting pain, stress or other cruelty on the donor animal)

As well of course, ol' toadfeatures bioassaying it, and seeing if it was indeed psychedelic, to provide more data as to the differential effects of functionally selective 5HT2a agonists in humano (or is that 'in demono-amphibio'? not sure of the latin adjective for transdimentional outer-god demon-toad deities ), with respects to psychedelic effectiveness (using 2,5-DMA as a counterpart, as a known functionally selective agonist going for the other second messenger intracellular metabolic pathway)

As I say, not an immediate priority for doing within days or weeks, etc, but certainly an idea that would be most fascinating to attempt, even if the correspondence with an established 'mainstream'  professional researcher who does the area of serotonergic psychedelics, could not be accomplished. Still, the results yielded from bioassay would be interesting to find out.

The reason for the inquiry as to use of a halex/finkelstein type reaction and its possibility, is to avoid the use for a potential synthesis of the volatile HCN, or cyanogen halides, etc. Potassium/sodium/copper/lead...insert metal here..cyanide is deadly, but if one has it sitting in crystalline form in a lab beaker, or in solution in a solvent, provided it is not spilled, and provided that acid is not allowed to contact it while there is unreacted cyanide in there, and provided it is neither ingested, contacted via inhalation as an aerosol somehow, nor spilled upon the skin, then it will not jump out and grab the experimenter and drop him dead.

Hydrogen cyanide gas on the other hand, or hydrocyanic esters, low molecular weight, volatile nitriles that are able to liberate cyanide ion in vivo metabolically, or the unstable, volatile and in general vicious, cyanogen halides can, and will liberate cyanide gas, or cyanogen/cyanogen halide fumes, and go about their merry murderous way. (not to mention the cyanogen halides are succeptible to explosive polymerisation, which would end up with both flying razor-sharp glassware bits going screaming through the air, and spraying a mixture of cyanogenic horror, precious, expensive reactant substrate (and almost certainly flammable and/or toxic) solvent through the air with extreme prejudice.

Not the sort of reaction Tsathoggua wants to be within a mile of, unless he was wearing a powered exoskeleton armor suit, with inbuilt rebreather and closed-circuit O2 source...even transdimentional, gigantic toad gods aren't indestructible, and have certain limits  

In what way?

Not very much if I have no idea what intent might be had towards its use...

What can I tell you now?

It should be crystalline, it will give a bright red color to any rxn mixture (at least I assume, as long as its soluable in said solvent system) containing ferric iron, the free thiocyanic acid is unstable, and almost certainly unobtainable in solution as free thiocyanic acid by addition of acid to its salts.

You could use it for synthesis, perhaps, of thiiranes, the sulfur homolog of an epoxide, after treatment with an appropriate glycol with phosgene (or phosgene equivalents, watch it with C=OCl2 its extremely toxic), or perhaps for the synthesis of the thioglycol homolog of ethylene glycol, which is a precursor for sulfur mustard agent (if you think phosgene is nasty......)

A solution of the stuff with an amine, acidified, should generate thiocyanic acid in-situ, and allow for preperation of thioureas.

No idea what hyppy is after though...or are you suggesting the possible idea of a thiocyanate substituted psychedelic amphetamine?

Thiocyanate isn't a rapidly lethal cytochrome oxidase-fucker, if thats what you mean, like the cyanide ion.

Purpose? well how can I tell you what you want from it....

Could be anything from mustard 'gas' to work on thiiranes. Hyppy could always cook some up, dissolve it in a fluoroalkane, with some added DMSO as an emulsion, perhaps, if possible, and aerosolize it in a police station.
That would be pretty funny.

You have been taking to much phenyl alanine by the sounds of it