starrfishes

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

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.
 

Requiem

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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

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Requiem said:
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.
 
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starrfishes

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inocenciotj said:
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

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