[n2ro]

Hi Everyone,

I'm looking for a solvent for a TLC experiment I am preparing for Organic 1.

I am trying to find a solvent that will provide good separation for benzoic acid, p-chlroanaline, and triphenyl methanol.

We have tried
- 30% 1-butanol + 70% cyclohexane + few drops of ammonia to make basic
- 50% ethyl acetate + 50% hexane

both have to large a gap with regards to the triphenyl methanol and are not suitable.

Any ideas or thoughts for a solvent?

Thanks!

[EdwardX]

48% toluene, 48% ethyl acetate, 4% acetic acid

[Babcock_Hall]

Would you explain why having too large a gap is a problem?  Why do you think that triphenylmethanol shows this behavior?

[n2ro]

I'm having trouble finding a solvent that doesn't virtually shoot the triphenylmethanol straight up off the paper, while keeping readable separation between all of the analytes.

[Babcock_Hall]

When I have multiple reactants and products that span a broad range of polarities, sometimes I use two separate solvent systems, designed to answer different questions.

[MOTOBALL]

Your first post talks about TLC, while your  lastt post mentios shooting off the paperr----which is it, paper or thin layer chromatography

[n2ro]

sorry it is TLC, meant to say sheets not paper.

[C-hemCards]

My 2 cents on this one: Virtually all compounds can be separated using one of the following solvent mixtures (ratios to be determined by you):

hexanes/EtOAc (the old stand-by)
CH2Cl2/Methanol (annoying)
CH2Cl2/Acetone (annoying and inconsistent due to acetone volatility)
MeOH/EtOAc (my favorite for polar compounds)

If you have highly acidic compounds, a 1% addition of AcOH is optional to tighten up a streaking spot.