I've been honing my TLC skills lately, and my latest reaction produces two isomers which are a little less polar than the starting material. The starting material dissolves nicely in ethyl acetate, chloroform, DCM but won't dissolve in acetone (and anything more polar) or hexane (and anything less polar).
Heres the results I've got so far:
100% ethyl acetate: all compounds run together with the solvent front, so I take it these compounds are extremely soluble in ethyl acetate
50:50 ethyl acetate:hexane: - I got one spot in the product lane, with a retention factor of about 0.9, it runs slightly ahead of the spot in the starting material lane which has an Rf of about 0.8
20:80 EtAc/n-hexane: Now two spots are visible in the product lane, but are very close together, and are followed very closely by the starting material spot. Bad separation and high Rf values of 0.7-0.5
10:90 EtAc/n-hexane: Slightly better separation, and Rf values between 0.6-0.3 but still pretty bad separation.
100% hexane: Starting material sticks to the baseline. Products separate nicely, but extremely slowly
So to try get better separation, I experimented with other solvents.
100% petroleum ether (40-60): More or less the same result as 100% hexane
100% DCM - The plate looked pretty much like 10:90 ethyl acetate:hexane. The same Rf values, the same separation.
50:50 DCM/hexane - Got a strange result with this one. All spots moved slow with an Rf of about 0.3, and no separation at all, even the starting material was indistinguishable from the products.
100% toluene - The whole plate (up to the solvent front at least) turned blue under UV, I mistakenly assumed that the mobile phase was contaminated with a UV-active compound (in reality what likely happened is I didn't let the plate dry, so it was the toluene that turned the plate blue) and threw the plate out after a quick glance but I could see a smeared spot in the product lane which moved really slowly, about 2 cm in 24 hours (I left the plate in overnight).
Thats what I've tested so far. My experience with mobile phases is extremely limited so I'd appreciate any tips, suggestions or if possible, info on what I can learn from the results I obtained. Based on something I read, I want to try using the 10:90 ethyl acetate:hexane system, but switching the non polar to another non polar. So 10:90 EtAc/toluene or EtAc/pet. ether.