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Chemistry Forums for Students => Organic Chemistry Forum => Topic started by: Amndz on October 23, 2011, 10:26:41 PM

Title: Yield improvement on vanillin reduction?
Post by: Amndz on October 23, 2011, 10:26:41 PM

How can the yield of a vanillin reduction lab be improved?
In my lab about .4g NaBH₄ was added to a chilled solution of 3g vanillin and 22mL NaOH, and about 10mL of 3M HCl was added in workup. I got a 72% yield, but I'm not sure how that could be improved.. How should I approach coming up with this?

 Thanks in advance!

Title: Re: Yield improvement on vanillin reduction?
Post by: orgopete on October 24, 2011, 08:11:12 AM

Check the stoichiometry.

Title: Re: Yield improvement on vanillin reduction?
Post by: Honclbrif on October 24, 2011, 08:53:32 AM

Was your product contaminated with unreacted starting material, or was it relatively pure but you just lost material along the way?

Title: Re: Yield improvement on vanillin reduction?
Post by: orgopete on October 25, 2011, 08:19:29 AM

I was looking at this from an atom efficiency point of view. I am presuming the reaction went to completion.

If you wish to improve the material balance, you could simply extract your alcohol from the reaction mixture. Semantically, that will improve your recovery. The yield can also be thought of as a function of the reaction.