O-chem lab TLC Question

[starrfishes]

This is a random o-chem lab question that I'm totally stuck with.

So my question is, how do we know if our reaction ran to completion for monitoring a ketone reduction reaction of Fluorenone to Fluorenol, with TLC (thin-layer chromatography)?

Do Rf factors help when the results show no big difference?

Is there any visible evidence that indicated the reaction went to completion?


Any help is greatly appreciated.

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[Requiem]

Well, upon TLC analysis did you have one, or two spots?

One spot would indicate the prescence of 1 compound -> completion.
2 spots -> 2 compounds -> Rx incomplete.

There will be a difference in the Rf values between the spots because there will be a different polarity acheived, therefore a different distance travelled up the sheet.

 

[inocenciotj]

Well, upon TLC analysis did you have one, or two spots?

One spot would indicate the prescence of 1 compound -> completion.
2 spots -> 2 compounds -> Rx incomplete.

There will be a difference in the Rf values between the spots because there will be a different polarity acheived, therefore a different distance travelled up the sheet.

And, if I might add... if u needed to identify which was which, fluorenol should have the lower Rf, since it can hydrogen bond.

 

[starrfishes]

And, if I might add... if u needed to identify which was which, fluorenol should have the lower Rf, since it can hydrogen bond.

Good point! I just noticed, after hours of staring at the book that compounds with greater polarity have a lower Rf. Thank you for your response, inocenciotj!

 

[starrfishes]

You guys are the greatest, thank you so much for the responses!!