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Help analyze HPLC/MS of fake 2c-i (actually 2c-b and something else)

I

intensecycle

Bluelighter
Joined
Aug 20, 2011
Messages
110
Maybe the unknown is 25BNBOMe, it's the right mass.

If the chromatography of my 25x looked like that I would return the stuff ASAP...
 
sekio said:
Maybe the unknown is 25BNBOMe, it's the right mass.

If the chromatography of my 25x looked like that I would return the stuff ASAP...
Click to expand...

The unknown with a peak at m/z = 340 is a dibrominated compound, so it is not 25BNBOMe. 25BNBOMe also should be at 365 (actually 364 and 366). Notice the m-2 and m+2 peaks at about 50% intensity, characteristic of a dibromo compound. Presumably the molecular ion for this is at 381 and 383, but that would only contain one bromine. What's odd is that the spectrum with the m/z 260 peak is the right nominal mass for the free base of 2C-B, but it should be a doublet with m/z of 259 and 261, not a single peak at 260, so I'm not sure if that's what it is. The fragments at 245 and 303 show the doublets expected for a brominated compound. The other compound with peaks at 274 and 276 looks like a monobromo compound, but DOB should be 273 and 275.:?
 
tryp2fun said:
The unknown with a peak at m/z = 340 is a dibrominated compound, so it is not 25BNBOMe. 25BNBOMe also should be at 365 (actually 364 and 366). Notice the m-2 and m+2 peaks at about 50% intensity, characteristic of a dibromo compound. Presumably the molecular ion for this is at 381 and 383, but that would only contain one bromine. What's odd is that the spectrum with the m/z 260 peak is the right nominal mass for the free base of 2C-B, but it should be a doublet with m/z of 259 and 261, not a single peak at 260, so I'm not sure if that's what it is. The fragments at 245 and 303 show the doublets expected for a brominated compound. The other compound with peaks at 274 and 276 looks like a monobromo compound, but DOB should be 273 and 275.:?
Click to expand...

it looks a mess but it fits for being DOB and some (quite a lot of) other junk. MS is Electrospray in positive mode so there should be M+H and as correctly pointed out there should be an M+H+2 to account for bromine isotopes, therefore 274 and 276 for DOB it is not a pretty chromatogram most likely it is a mixture of DOB and possibly 2-CB, about 60% DOB
it is junk
 
vecktor said:
it looks a mess but it fits for being DOB and some (quite a lot of) other junk. MS is Electrospray in positive mode so there should be M+H and as correctly pointed out there should be an M+H+2 to account for bromine isotopes, therefore 274 and 276 for DOB it is not a pretty chromatogram most likely it is a mixture of DOB and possibly 2-CB, about 60% DOB
it is junk
Click to expand...

OK, it wasn't clear to me that it was electrospray ionization, so it clearly contains DOB. The other component with the 260 m/z peak (and 262?) could also be some O-demethylated DOB rather than 2C-B. Why mix 2C-B and DOB? HBr can demethylate aryl methyl ethers if the reaction gets hot.
 
The MS is not enough your friend made a few common mistakes:
1. Absolutely no idea if this is the spectra for just the injection period
2. He completely forgot isotope limits which are pretty important most software has ultra mass accuracy on the isotopes to very low decimal places so you can compare i.e lets say you get 235.085 for a random compound as the true ionization mass, but your predicted mass is 235.099, its extremely important you understand if you are working with halogens and their respective isotopes because this effect can determine if it is a random noise from the background or your compound
3. Just because something shows up on the mass spectra unless you investigate just the injection period then you have no idea what is what, also unless you have reasonable isotope limits that can detect APPROXIMATE limits on each peak- they are just numbers, unless you want to calculate them all- its pointless most are DEFINITELY NOISE. Remember the relationships between accuracy, resolution, signal and noise!
4. Have your friend consider these then zoom in on the 100-300 m/z region
5. Note that the % composition is relative to other peaks in the given plot, if you zoom in on any peak that did not appear as 100% initially you will notice it can be 100% because it is a relative % to the plot.

From this mass spectra unless you find out more data YOU CANNOT conclude what it is. Yes you can guess but still sorry redo this or check on the criteria
zedsdead
 
going to throw out another idea, the data fits with BK 2-CB which of course is practically the same mass as DOB, plus using acid base to prep the sample would give a mixture of dimers and ring closed dimeric piperazine, which would approx weigh 2x as much but would also be doubly charged, so give similar m/z more importantly the signature +2 amu pair of bromine containing molecules would then be +1 amu which is what we see for the peak identified as 2cb. I can't be bothered to work out the numbers.
I have no idea what the +ESI spectra of dimeric cathinones looks like, it would i guess depend on the voltage and flow rates as well as how aqueous the mobile phase was and what else was present. The dimer would be prone to fragmentation in the source.
it looks also like the synthesis was botched in any case.
given bk 2cb is available and cheap its substitution for other more expensive materials is probably going to occur.

in the case above a simple marquis formaldehyde sulphuric acid color test would establish the likely presence of bk 2cb

in any case it is not 2CI
 
welcome back!
also, sounds like a good hypothesis.

ebola
 
there is alot of this going on with "vendors" seems like there should be more quality control implemented by the community.
 
To be fair, most of the "vendors" I see are quite obviously not legit chemical companies. (This is why I never really buy the "I bought this from a trusted vendor!!!!!!!" excuse.)
 
This last part I understand quite well and it seems to be very true.
 
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