LC-MS Benzyl Chloride Determination

[Mr Vapour]

Hi all, I'm trying to study the detection of Benzyl Chloride by LC-MS. Analytically the column and separation method works (210 nm) but I have difficult in Mass detection - I work with ESi(+/-) source and I find M-H+ of 242. Any advise for me in ionisation conditions and mass detection?

[Rndirk]

Benzyl chloride has a molar mass of 126,58 g/mol. Unless you derivatize, you're looking at the wrong peak. It will be very hard to get a good signal for such a small molecule, virtually unable to carry a charge in solution, in LC-ESI-MS.

Gas chromatography looks much better for this compound.

[Mr Vapour]

Oh thanks. I'm working on an API very very low soluble in most part of solvents suitable in HS-GC. The only conditions suitable are aqueous basic environment (pH ab. 12) and benzyl chloride hydrolize to benzyl alcohol or acidic conditions (pH 1). I don't have access to GC-MS.- The ESI mass probably the only solution to go down 5 ppm. =((

[Rndirk]

Is LC-APCI-MS an option?

Benzyl alcohol could give you a signal in ESI-MS. Optimize the conditions by infusion of the compound you're going to detect.

[Mr Vapour]

No, APCI is not available. I generally work on small molecules, as impurities of synthesis. I'm trying to improve my experience and I also have problems in optimizing the ionization conditions for hydroxybenzaldehyde and similar by ESI(+/-) source. I need to have literature and material for LC-MS determination of small molecules with my LC-MS.

[HPLC chemist]

I developed a method for Benzyl Alcohol and its related substances using a PDA. If you are not getting an appropriate signal with MS why are you insisting on using MS?